[win32] remove non-existing header files from project files

Stops projects from always being built in VS when nothing changed.
[win32] git_revision custombuild trigger from existing file, set correct outputpath, remove non existing dependency.
[win32] remove redundant /MP compiler option in release builds.

The duplicate /MP option (listed in "Additional Options" and also enabled with the "Multi-processor Compilation" option) was causing a full rebuild because msbuild is removing the duplicate from the commandline causing:
"Forcing rebuild of all source files due to a change in the command line since the last build."
Merge pull request #5841 from chadoe/headercleanup

[win32] Headerfiles/compiler settings cleanup