Add recurring issues for troubleshooting

Hopefully alleviates new issues getting created for similar problems. 
Addresses facebook#257 facebook#304 facebook#306 facebook#326

docs/Troubleshooting.md

@@ -0,0 +1,43 @@
+---
+id: troubleshooting
+title: Troubleshooting
+layout: docs
+category: Quick Start
+permalink: docs/troubleshooting.html
+---
+
+## Cmd-R does not reload the simulator
+Enable iOS simulator's "Connect hardware keyboard" from menu Hardware > Keyboard menu. 
+
+![Keyboard Menu](https://cloud.githubusercontent.com/assets/1388454/6863127/03837824-d409-11e4-9251-e05bd31d978f.png)
+
+
+If you are using a non-QWERTY/AZERTY keyboard layout you can use the `Hardware > Shake Gesture` to bring up the dev menu and click "Refresh"
+
+## Port already in use red-screen
+![red-screen](https://cloud.githubusercontent.com/assets/602176/6857442/63fd4f0a-d3cc-11e4-871f-875b0c784611.png)
+
+
+Something is probably already running on port 8081. You can either kill it or try to change which port the packager is listening to.
+
+### Kill process on port 8081
+`$ sudo lsof -n -i4TCP:8081 | grep LISTEN`
+
+then
+
+`$ kill -9 <cma process id>`
+
+
+
+### Change the port in Xcode
+Edit `AppDelegate.m` to use a different port.
+```
+  // OPTION 1
+  // Load from development server. Start the server from the repository root:
+  //
+  // $ npm start
+  //
+  // To run on device, change `localhost` to the IP address of your computer, and make sure your computer and
+  // iOS device are on the same Wi-Fi network.
+  jsCodeLocation = [NSURL URLWithString:@"http://localhost:9381/index.ios.bundle"];
+  ```