Change bindings to build from newer libinjection fork

[veeshi]

The current version of libinjection is built from client9/libinjection which was last updated on Mar 12, 2018.

There is a newer fork libinjection/libinjection which, at the time of writing, has a few changes and bug fixes, with the latest commit being 14 days ago.

[fzipi]

Just to add more context, this was indeed transferred in client9/libinjection#150 (comment).