Updated release notes.

Solution file supports VS2013.

Solution file now compatible with VS2013.  Backwards compatible with
VS2012 and VS2010 SP1.  Removing provided VS2008 solution.

Fixed text rendering issue on document tabs.

2.8 final.

Release version 2.7

Release 2.6

2.5 Release Candidate 1.

Release 2.4

Release 2.3.1.

Release 2.3