Use HTTPS, link Java 8 docs instead of 6 and fix invalid links.

build.gradle

@@ -29,15 +29,15 @@ allprojects {
 		}
 
 		maven {
-			url 'http://maven.sk89q.com/repo'
+			url 'https://maven.sk89q.com/repo'
 		}
 
 		maven {
 			url 'https://papermc.io/repo/repository/maven-public/'
 		}
 
 		maven {
-			url 'http://ci.emc.gs/nexus/content/groups/aikar/'
+			url 'https://ci.emc.gs/nexus/content/groups/aikar/'
 		}
 
 		maven {

src/main/java/ch/njol/skript/SkriptConfig.java

@@ -155,7 +155,7 @@ public DateFormat convert(final String s) {
 					return null;
 				return new SimpleDateFormat(s);
 			} catch (final IllegalArgumentException e) {
-				Skript.error("'" + s + "' is not a valid date format. Please refer to http://docs.oracle.com/javase/6/docs/api/java/text/SimpleDateFormat.html for instructions on the format.");
+				Skript.error("'" + s + "' is not a valid date format. Please refer to https://docs.oracle.com/javase/8/docs/api/java/text/SimpleDateFormat.html for instructions on the format.");
 			}
 			return null;
 		}

src/main/java/ch/njol/skript/effects/EffExplosion.java

@@ -37,7 +37,7 @@
  * @author Peter Güttinger
  */
 @Name("Explosion")
-@Description({"Creates an explosion of a given force. The Minecraft Wiki has an <a href='http://www.minecraftwiki.net/wiki/Explosion'>article on explosions</a> " +
+@Description({"Creates an explosion of a given force. The Minecraft Wiki has an <a href='https://www.minecraftwiki.net/wiki/Explosion'>article on explosions</a> " +
 		"which lists the explosion forces of TNT, creepers, etc.",
 		"Hint: use a force of 0 to create a fake explosion that does no damage whatsoever, or use the explosion effect introduced in Skript 2.0.",
 		"Starting with Bukkit 1.4.5 and Skript 2.0 you can use safe explosions which will damage entities but won't destroy any blocks."})

src/main/java/ch/njol/skript/expressions/ExprGlidingState.java

@@ -31,7 +31,7 @@
 import ch.njol.skript.expressions.base.SimplePropertyExpression;
 
 @Name("Gliding State")
-@Description("Sets of gets gliding state of player. It allows you to set gliding state of entity even if they do not have an <a href=\"http://minecraft.gamepedia.com/Elytra\">Elytra</a> equipped.")
+@Description("Sets of gets gliding state of player. It allows you to set gliding state of entity even if they do not have an <a href=\"https://minecraft.gamepedia.com/Elytra\">Elytra</a> equipped.")
 @Examples({"set gliding of player to off"})
 @Since("2.2-dev21")
 public class ExprGlidingState extends SimplePropertyExpression<LivingEntity, Boolean> {

src/main/java/ch/njol/skript/expressions/ExprProtocolVersion.java

@@ -41,7 +41,7 @@
 
 @Name("Protocol Version")
 @Description({"The protocol version that will be sent as the protocol version of the server in a server list ping event. " +
-		"For more information and list of protocol versions <a href='http://wiki.vg/Protocol_version_numbers'>visit wiki.vg</a>.",
+		"For more information and list of protocol versions <a href='https://wiki.vg/Protocol_version_numbers'>visit wiki.vg</a>.",
 		"If this protocol version doesn't match with the protocol version of the client, the client will see the <a href='#ExprVersionString'>version string</a>.",
 		"But please note that, this expression has no visual effect over the version string. " +
 		"For example if the server uses PaperSpigot 1.12.2, and you make the protocol version 107 (1.9),",

src/main/java/ch/njol/skript/hooks/regions/GriefPreventionHook.java

@@ -81,7 +81,7 @@ protected boolean init() {
 		} catch (final NoSuchFieldException e) {} catch (final SecurityException e) {}
 		if (getClaim == null && claimsField == null) {
 			Skript.error("Skript " + Skript.getVersion() + " is not compatible with GriefPrevention " + plugin.getDescription().getVersion() + "."
-					+ " Please report this at http://dev.bukkit.org/bukkit-plugins/skript/tickets/ if this error occurred after you updated GriefPrevention.");
+					+ " Please report this at https://github.com/SkriptLang/Skript/issues/ if this error occurred after you updated GriefPrevention.");
 			return false;
 		}
 		return super.init();

src/main/java/ch/njol/skript/util/chat/ChatCode.java

@@ -21,8 +21,8 @@
 import org.eclipse.jdt.annotation.Nullable;
 
 /**
- * Chat codes; includes color codes (<a href="http://wiki.vg/Chat#Colors">reference</a>)
- * and also, some formatting codes (mostly <a href="http://wiki.vg/Chat">this</a>)
+ * Chat codes; includes color codes (<a href="https://wiki.vg/Chat#Colors">reference</a>)
+ * and also, some formatting codes (mostly <a href="https://wiki.vg/Chat">this</a>)
  */
 public interface ChatCode {
 

src/main/java/ch/njol/skript/variables/DatabaseStorage.java

@@ -165,7 +165,7 @@ protected boolean load_i(final SectionNode n) {
 		synchronized (db) {
 			final Plugin p = Bukkit.getPluginManager().getPlugin("SQLibrary");
 			if (p == null || !(p instanceof SQLibrary)) {
-				Skript.error("You need the plugin SQLibrary in order to use a database with Skript. You can download the latest version from http://dev.bukkit.org/server-mods/sqlibrary/files/");
+				Skript.error("You need the plugin SQLibrary in order to use a database with Skript. You can download the latest version from https://dev.bukkit.org/projects/sqlibrary/files/");
 				return false;
 			}
 

src/main/resources/config.sk

@@ -93,7 +93,7 @@ use player UUIDs in variable names: false
 date format: default
 # The date format to be used when dates should be displayed.
 # This can be 'default' to use Java's default date format for the system's language.
-# The format is that of Java's SimpleDateFormat as defined here: http://docs.oracle.com/javase/6/docs/api/java/text/SimpleDateFormat.html
+# The format is that of Java's SimpleDateFormat as defined here: https://docs.oracle.com/javase/8/docs/api/java/text/SimpleDateFormat.html
 # some examples:
 #  d/M/yyyy h:mm a => 15/7/2012 8:53 PM
 #  dd.MM.yyyy, HH:mm => 16.03.2013, 09:33

src/main/resources/lang/readme.txt

@@ -26,7 +26,7 @@ You can either put language files into the lang folder in the jar or into the pl
 (If there are two files for the same language both will be loaded but the file in the folder will overwrite values from the file in the jar)
 The exception to this rule is the default english file which is only loaded from the jar.
 
-Strings that have arguments use Java's formatter syntax, see http://docs.oracle.com/javase/6/docs/api/java/util/Formatter.html#syntax.
+Strings that have arguments use Java's formatter syntax, see https://docs.oracle.com/javase/8/docs/api/java/util/Formatter.html#syntax.
 
 Nouns have special syntax to define their plural and gender:
 	Plurals are defined like in aliases.sk: 'name¦s' / 'shel¦f¦ves' / 'word¦¦s¦ of power'