BIASEXCHANGE now working with GMX461
Merge branch 'v2.0'
Merge branch 'v2.0'
Merge branch 'v2.0'
Merge branch 'v2.0'
Removed unecessary and memory expensive lists

This mostly affects stuff in crystallization.  The only thing in the
version 2.0 branch that this could improve is if you are doing
moments of distributions with very large numbers of collective
variables.  i.e. it would affect the following command

COORDINATIONNUMBERS SPECIES=1-10000 MOMENTS=2-3 etc
Changed interface between MultiColvar and MultiColvarFunction

These changes allow more flexility when we use functions of the set
of quantities calculated by MultiColvar.
Merge branch 'v2.0'
Merge branch 'v2.0'
Merge branch 'v2.0'
Merge branch 'v2.0'
Merge branch 'v2.0'
Merge branch 'v2.0'
Added file for master-only CHANGES
Merge branch 'v2.0'
Merge branch 'v2.0'
Fixed virial contribution in ActionVolume.

This is only important if using non-subcell volumes.  If you use subcell the virial
is zero
Merge branch 'master' of git.assembla.com:plumed2
Merge branch 'v2.0'
Merge branch 'v2.0'