support for windows in ChangeAgentTools

The windows Symlink function checks for the existance of the source file before creating a symlink. If it cannot stat the file, then it errors. This is a limitation of how junction points work. You may not create a junction point (symlink) to an inexistent file.
Sorry for the late response. The test was changed to use absolute paths because the function was changed to set an absolute path to the symlink. This is consistent with the way it must be done on Windows. On windows, symlinks (junction points) always return absolute paths.