Adds cut-off checks for triclinic domain decomposition

With domain decomposition and 2 decomposition cells in a trilinic
dimension, the cut-off could be longer than the size of the
communicated domains. This could lead to some pairs close to cut-off
distance to be ignored in the force/energy calculations.
Fixes #1467

Change-Id: Id7e16d7f8fa0796d6adcf48ad6e8bbb0b88039ff
Make sure water optimization is disabled for esoteric interactions

This fixes a bug where the generic NB kernel could be called with
a water-water neighborlist for a few special combinations where
no C kernels existed (e.g. switch/shifted plain-cutoff coulomb).
This would typically lead to virtually no nonbonded interactions
being calculated and the simulation crashing rapidly, so it is
unlikely to have affected any results silently, but was noticed
when testing interaction forms.

Change-Id: I634fc4ab78b54281c89333299975e25883dc1f2c
Fix invalid dereference in g_tune_pme

Change-Id: If4c999e22799ab2087ff1a1d74d8e5b50ddddd57
Merge branch 'release-4-6' into release-5-0

Change-Id: Icd1eafab98512328523a3ea788626b3fb415b0a8