Update README.md with grammar changes.

Updated README.md with grammar changes such as "is" to "are" and preventing unnecessary run-on sentences.

README.md

@@ -1,6 +1,6 @@
 # Material design icons
 
-Material design icons are the official [icon set](https://www.google.com/design/spec/style/icons.html#icons-system-icons) from Google that are designed under the [material design guidelines](https://material.io/guidelines/).
+Material design icons is the official [icon set](https://www.google.com/design/spec/style/icons.html#icons-system-icons) from Google.  The icons are designed under the [material design guidelines](https://material.io/guidelines/).
 
 ### 3.0.1 Update
 
@@ -36,5 +36,5 @@ If you wish to use the icon set with Polymer, we recommend consuming them via th
 
 ## License
 
-We have made these icons available for you to incorporate them into your products under the [Apache License Version 2.0](https://www.apache.org/licenses/LICENSE-2.0.txt). Feel free to remix and re-share these icons and documentation in your products.
+We have made these icons available for you to incorporate into your products under the [Apache License Version 2.0](https://www.apache.org/licenses/LICENSE-2.0.txt). Feel free to remix and re-share these icons and documentation in your products.
 We'd love attribution in your app's *about* screen, but it's not required. The only thing we ask is that you not re-sell these icons.