adding -f flag to stop 'patch' from asking any question

[waleedq]

Sometimes the --dry-run will go into interactive mode to ask if these patches are Reversed or not, using -f flag would force 'patch' to stop asking any question and return the result from --dry-run.

As documented in patch man-pages

-f or --force
Assume that the user knows exactly what he or she is doing, and do
not ask any questions. Skip patches whose headers do not say
which file is to be patched; patch files even though they have the
wrong version for the Prereq: line in the patch; and assume that
patches are not reversed even if they look like they are. This
option does not suppress commentary; use -s for that.

Creating this pull request so it can update PR in cweagans#202.

Thank You.