cmDependsC: Collapse relative include paths

While calculating dependencies collapse sequences such as

 ../../../a/b/c/../../d/e/../../e/f

to avoid total path lengths over the Windows path length limit as much
as possible.
FindGTK2: Do not fail on MSVC11 if vc100 libraries are available
FindGTK2: Add GTK2_DEFINITIONS variable

According to https://wiki.gnome.org/gtkmm/MSWindows on MSVC the /vd2
flag should be passed to the compiler in order to use gtkmm
KWSys 2013-07-01 (f6c4c247)

Extract upstream KWSys using the following shell commands.

$ git archive --prefix=upstream-kwsys/ f6c4c247 | tar x
$ git shortlog --no-merges --abbrev=8 --format='%h %s' 3d1d4e7c..f6c4c247
Sean McBride (1):
      f6c4c247 RegularExpression: Remove 'register' storage specifier

Change-Id: I755712879ab86fa163f5fce684fff2f0ecd8ab99
Merge branch 'upstream-kwsys' into update-kwsys
Fortran: Use explicit type in Fortran 90 check

In CMakeTestFortranCompiler we build a test program using a Fortran 90
construct to check whether the compiler supports the language.  Some
compilers have options to require explicit variable types.  Fix the test
program to use an explicit variable type so it passes under such a
configuration.

Suggested-by: Neil Carlson <neil.n.carlson@gmail.com>
SelectLibraryConfigurations: Fix for cached <base>_LIBRARY

The line

  set( ${basename}_LIBRARY )

removes the normal variable, but if the corresponding cached variable is
present then line

  list( APPEND ${basename}_LIBRARY optimized "${_libname}" )

uses that and fails.  Replace the original line with

  set( ${basename}_LIBRARY "" )

to set the normal variable to empty instead of unsetting it.
VS: Clarify Visual Studio product year for each version

Add to the brief documentation of the Visual Studio 10, 11, and 12
generators the corresponding VS product year.  Clarify that VS11 is for
Visual Studio 2012, and VS12 is for Visual Studio 2013.
Merge topic 'vs-generator-brief-doc-update'

52f1464 VS: Clarify Visual Studio product year for each version
Merge topic 'SelectLibraryConfigurations-cached-library'

c4bcc56 SelectLibraryConfigurations: Fix for cached <base>_LIBRARY
Merge topic 'make-depends-collapse-paths'

551d334 cmDependsC: Collapse relative include paths
Merge topic 'FindGTK2vs11'

eb16301 FindGTK2: Do not fail on MSVC11 if vc100 libraries are available
Merge topic 'FindGTK2vd2'

60e4555 FindGTK2: Add GTK2_DEFINITIONS variable
Merge topic 'update-kwsys'

c314da0 Merge branch 'upstream-kwsys' into update-kwsys
2e3c935 KWSys 2013-07-01 (f6c4c247)
Merge topic 'Fortran-explicit-types'

7b5bc2c Fortran: Use explicit type in Fortran 90 check