Create Visual Studio 2010+ compatible solutions and projects when generating
projects for VS 2012 and later. This introduces/fixes support for the Visual
Studio '14' compile chain's projects via the 'fallback' 14 behavior.

As the current estimated release time for VS '14' is 2015 at earliest, I'm
not adding a more specific name yet.

* build/generator/gen_win_dependencies.py
  Make regex matches for deprecated versions a bit stricter. Fix vsversion
  typo.

* build/generator/templates/vcnet_sln.ezt
  Generate compatible versions header, specifying compatibility with VS 2010
  SP 1 (which introduced support for the 12.0 format, really added in VS2012).


git-svn-id: https://svn.apache.org/repos/asf/subversion/trunk@1601851 13f79535-47bb-0310-9956-ffa450edef68