BUG: If the destination is the same as source, do not copy file. Fixes Bug #956 - make install broken

ENH: add CMAKE_FILE_PATH, CMAKE_PROGRAM_PATH, CMAKE_LIBRARY_PATH, and search them first, PATH second, and last the paths listed in the FIND call

BUG: Replace MATCHES with STREQUAL for better checking, better checking for existence of swig directory, verify if required flag was set, support fedora's location of swig. Fixes Bug #955 - Swig on fedora and Bug #954 - FIND_PACKAGE(SWIG REQUIRED)

BUG: exec program should not fail if it can not exec the program, but should only set the return value to -1 and set the output to the reason for the failure.

BUG: fix spaces in path on mingw, and change EXEC_PROGRAM to return false when it does not run, also do not convert the directory to an output path for EXEC_PROGRAM as this is done by the process execution, and doing it twice may cause trouble on some shells.

BUG: Added special hack for VTK 4.0-4.4 to re-enable automatic addition of current source directory to -I path.

BUG: Need to preserve automatic addition of source tree to -I path if CMAKE_BACKWARDS_COMPATIBILITY is set to below 2.0.

This is not consistent with the Visual Studio generators which do not
provide this path.  It should not be added anyway because it is adding
an include path not requested by the CMakeLists.txt code.  The code I'm
removing was originally added in revision 1.17 of cmUnixMakefileGenerator.cxx
as a part of several other changes and has a commit log entry of

  "some bug fixes"

It was propagated from their to cmLocalUnixMakefileGenerator.cxx.
Since all our projects build in the VS IDE without this include path, it should not be needed.  Users can easily fix problems caused by this by adding

  INCLUDE_DIRECTORIES(${CMAKE_CURRENT_SOURCE_DIR})

to their CMakeLists.txt code.  This was often necessary previously when a
project was originally written on a Unix system and then built with
Visual Studio.