git.exe location cannot be specified

[randomascii]

When using the -verifyLocalRepo option, which is necessary to avoid losing the case of source files, git.exe cannot easily be found. The FindGitExe function looks in a few hard-coded locations but does not look in the path and there is no option to specify the location of git.exe. I had to edit the script and explicitly say the location of the executable in order for this to work.

The script should look in all directories in the path, and should have an option to specify the location of git.