Switched the ToolsVersion attribute to 4.0 to support Xamarin Studio and Mono
Ignored Xamarin Studio preferences and fixed a typo in the project file for P5
Starting fresh…
Removed the solution.
Added in a clean solution file
Shifted to Xamarin / Mono compatible formats.
Added in the beginning of problem 12
Merge branch 'feature/P12'

* feature/P12:
  Added in the beginning of problem 12
  Shifted to Xamarin / Mono compatible formats.
  Added in a clean solution file
  Removed the solution.
  Starting fresh…
  Ignored Xamarin Studio preferences and fixed a typo in the project file for P5
  Switched the ToolsVersion attribute to 4.0 to support Xamarin Studio and Mono

Conflicts:
	.gitignore