[FEATURE REQUEST] Patch AUR directory

[MaFeLP]

Add command line argument -p which accepts a .patch file generated by GNU diffutils When installing/upgrading a package.

This file should be able to modify the directory after the clone from the AUR and before the package is being built.

[lxgr-linux]

I won't implement this via a command line argument, because at updates and when installing more than one package this may lead to problems. But I will figure out something else.