Add .gitattributes

- Normalize line-endings to LF when checked into the repository. Doesn't
  touch the working copy.

  http://git-scm.com/docs/gitattributes#_end-of-line_conversion

- Language-aware diffs.

  http://urbanautomaton.com/blog/2011/07/28/git-grep-and-language-specific-diffs/

- Run 3-way file level merge for project files, but take lines from both
  versions, instead of leaving conflict markers. This tends to leave the
  added lines in the resulting file in random order and the user should
  verify the result.

  http://git-scm.com/docs/gitattributes#_performing_a_three-way_merge
Slightly improve the readme

- Remove the first paragraph from under the first heading saying how the
  project and its website are open source. It's pretty obvious since it's on
  GitHub.

- Tell people to enable NuGet package restore on Visual Studio.
Add "coding style" section to the readme
Add "obj", ".nuget" and "*.suo" to .gitignore