Fix problem with libtidy
Fix csproj files

- don't try to use Windows copy command
  on Linux
- copy libtidy to output directory
- ignore *.userprefs files
- use hardcoded output path instead of
  variable in BloomTests.csproj so that
  debugging works in MonoDevelop
- add TidyManaged config file which maps
  libtidy.dll to the correct shared library
Reopen linux branch
Adding .gitattributes and .gitignore files