Fix a pixmap leak in the ms-windows engine

This was pointed out in https://bugzilla.gnome.org/show_bug.cgi?id=731967.
Include image data in the builtin icon cache
2.24.24
Fix "Installation" for Visual Studio 2010+

We need to enclose paths containing $(BinDir) with double quotes as it
points to something like c:\foo\gtk+-x.yy.zz, which the copy command on
Windows does not like "+" in paths unless enclosed in quotes.
Build: Provide Simple Support for MSVC 2012/2013

As the Visual Studio 2012/2013 are only slightly different from the Visual
Studio 2010 projects, we can provide support for them by using scripts to
copy the Visual Studio 2010 projects, and update the specific parts as
necessary.  This is being provided to help people still needing GTK+-2.x
and also to help them to transition to GTK+-3.x easier.

Thus, there would be little maintenance overhead for these as only the 2010
projects need to be kept up-to-date as a result.  This might change when we
do get the stack working with WinRT/Metro, but that's going to be another
totally different issue.
Merge branch 'gtk-2-24' of git://git.gnome.org/gtk+ into gtk-2-24