[Proj] SO names in 4.9.1 and current trunk

[Sebastiaan Couwenberg]

> Is anyone else seeing a change in the naming of shared objects?

Yes, 4.8.0 broke the ABI compatibility and 4.9.0 did too, so a SONAME bump
is required.

http://upstream.rosalinux.ru/versions/libproj.html

This issue was raised on this list before, see:

http://lists.maptools.org/pipermail/proj/2015-March/007056.html
http://lists.maptools.org/pipermail/proj/2015-February/006992.html

Kind Regards,

Bas