Add FindPatch.cmake

FindPatch.cmake is used on Windows (MSVC) platforms to find patch.exe.
It currently only looks in msysgit/bin (and system paths) but this can
be easily extended.

PATCH_SCRIPT_PATH is now used to specify the location of patch.sh/bat.
As such SCRIPT_PREFIX has been removed.

Rationale for change:
* Modifying your path may require admin permissions for MSVC
* CMake now exits with an error message on MSVC if patch.exe cannot be
found
* Fewer manual steps when setting up Desurium on MSVC
Remove reference to TortoiseGit

TortoiseGit does not include patch.exe as indicated (msysGit does
however) and as such is superfluous.
Correct reference to Patch.bat

I missed a reference to patch.bat in commit
6d5aeb3607460ecf3a41947a0621862cb654c1de.
Substitute @...@ with ${...} in Patch.bat

This should improve readibility.
Check for patch on all systems

Ensure patch is available (and exit with an error if it can't be found).
Move patch.bat into CMAKE_GEN_SRC_DIR/scripts
Change Find(MFC) to run earlier

MFC_FOUND was checked before Find_package(MFC) was run. This caused
CMake to always assume MFC was missing.
Ensure MFC is used for DesuraMain.cpp
fix indenting of bootloader_win/CMakelists.txt
Ensure Breakpad builds with MD

By default breakpad builds with MD and there appears to be no way of
changing this behaviour. As such we directly patch the generated vcxproj
file.
link mdump against bootloader_win

bootloader_win reports missing symbols without mdump
Build boost test library under Windows

Boost test libraries where not being built causing compilation to fail.
Replace breakpad-VS.patch with cmake script

The CMake script uses regular expressions to set the correct
RuntimeLibrary. This should be a bit more robust then using a patch.
Merge pull request #489 from harmonise/VS_library_fixes

VS library fixes
Merge pull request #475 from harmonise/FindPatch

add FindPatch.cmake
PKGBUILDs: remove unneeded (make)dependencies.
Merge pull request #492 from matthiaskrgr/PKGBUILD_Deps

PKGBUILDs: remove unneeded (make)dependencies.
gitignore: add build_package folder.
build_desura.sh: add missing exit status.
install_deps.sh: note pack_deb/rpm options if we are on debian/redhat