Add script which can fix the broken commits in this repository

Note the resulting hashes are (of course) different.
Merge pull request #117 from djs55/fix-broken-commits

Add script which can fix the broken commits in this repository
Makefile changes.

Signed-off-by: John Else <john.else@citrix.com>
Add bindings for xc_[gntshr|gnttab]_[open|close] and helper functions.

Signed-off-by: John Else <john.else@citrix.com>