Bump shared object version to 7

Almost certainly the ABI is binary incompatible for the 4.5.5 -> 4.5.6
transition, but we didn't think of handling the issue at the time.
So we can do so now.

Refs #1147

Change-Id: I15f978547d7fbcc9a72454067825c71c0ffb459a
Fixes #1183 PBC bug in g_mindist

Fixes minimum size of the box if triclinic when checking
the periodic image distance.

Change-Id: I54cb593c42f791b6540147233c345069f84e2f33
Merge release-4-5-patches into release-4-6

Conflicts:
	CMakeLists.txt
	configure.ac
	src/tools/gmx_mindist.c

Change-Id: I303318f17527a8e1bfe494eb174565b8d5491870
Merge "Merge release-4-5-patches into release-4-6" into release-4-6