cmake/cef: fix build on win32

v2: fix build error on Linux
cmake: install built wxWidgets libs on win32
cmake/win: add windows SDK and target definitions

we need a windows Vista SDK and want to target Windows XP SP2
cmake: add specific MFC stuff and clean up target definitions
repair stuff I broke in the past
managers: fix singleton mutex on win32
uicore: fix theme loading problems on win32
servicecore: fix mcfcore library loading on win32
bootloader_win: fix path and names of libs
serivce_win: fix desura.exe call
service_win: use binary name used by desura
service_win: fix dll loading on win32
serivce_win: check cert only on official build
cmake: don't install Unix tools on Win32
util/os: add getMcfCachePath() and use it
usercore: use same function to get Application path for win32 and Unix
util: implement getCachePath and getAppInstallPath on win32

fixes #583
readme: update with newest win32 instructions
Fixed NSS 3.15 errors.