README.md updates

- Call out the prerequisites at the top level.
- Reflow text to wrap at 80 columns when possible.

Author: ellismg

README.md

@@ -5,6 +5,14 @@ follow our coding styles, which are [documented here][corefx-coding-style].
 
 [corefx-coding-style]: https://github.com/dotnet/corefx/wiki/Contributing#c-coding-style
 
+## Prerequisites
+
+In order to build or run this tool you will need to have Microsoft Build Tools
+2015 Preview installed.  This comes as a part of Visual Studio 2015 Preview or
+can be installed separately from [here][vs-2015-download].
+
+[vs-2015-download]: http://www.visualstudio.com/en-us/downloads/visual-studio-2015-downloads-vs)
+
 ## Usage
 
 In order get the usage, simply invoke the tool with no arguments:
@@ -17,10 +25,9 @@ CodeFormatter <solution> [<rule types>] [/file <filename>]
     <filename> - Only apply changes to files with specified name.
 ```
 
-Note: In order to run this tool you will need to have Microsoft Build Tools 2015 Preview installed.  This comes as a part of Visual Studio 2015 Preview or can be installed separately from [here](http://www.visualstudio.com/en-us/downloads/visual-studio-2015-downloads-vs).
-
 ## Contributing
 
-We follow the same contribution process that [corefx is using][corefx-contributing].
+We follow the same contribution process that 
+[corefx is using][corefx-contributing].
 
 [corefx-contributing]: https://github.com/dotnet/corefx/wiki/Contributing