pjproject_bundled: Move to pjproject 2.5

Although all the patches we had against 2.4.5 were applied by Teluu,
a new bug was introduced preventing re-use of tcp and tls transports
This patch removes all the previous patches against 2.4.5, updates
the version to 2.5, and adds a new patch to correct the transport
re-use problem.

Change-Id: I0dc6c438c3910f7887418a5832ca186aea23d068