Unlike previous versions of Visual Studio the VC12 solution file format
does not increment the format version number, but instead, only changes
the version comment text.
This incorrectly set version number would cause problems for any third
party piece of software that would read the solution file expecting the
version number to be 12.00 and found it to be 13.00, such as some build
accelerators.
Verified against a freshly created solution file which was generated
with VC12.
Carrying on from commit 11025613b9 added VC12 project files which are
capable of supporting side-by-side compilation, 32-bit and 64-bit
builds as well as support for some of the third-party libraries curl
uses.
