the new organisatoion of the gromacs source code allows simplifying
our patch. Multi-sim is now tested at least for multiple walkers
metad

on a single aladp metadynamics (that works)
more test are needed
- parallel stuff
- replica exchange
- hrex
- gpu

this is not really working yet, but hopefully we are not far

(backported from v2.5)

no actual change

See #414

It should prepend the libplumed.so library with prefix -Wl,
so as not to disturb NAMD makefile. (suggested by @jcphill)

update GMX2018.3 accordingly
- including API check

see #227

Thanks @hanatok!

it includes an additional modification to keep multisim in sync when using plumed

When doing plumed patch -e gromacs2016.5 a match with e.g. gromacs2016.4
will be accepted (and issue a WARNING). Useful for automatized patching
procedures.

For instance, in gromacs-plumed package of MacPorts it won't be necessary
to synchronize the Portfile with the exact plumed version.

When doing plumed patch -e gromacs2016.5 a match with e.g. gromacs2016.4
will be accepted (and issue a WARNING). Useful for automatized patching
procedures.

For instance, in gromacs-plumed package of MacPorts it won't be necessary
to synchronize the Portfile with the exact plumed version.

Slow implementation, calls scripts everytime

Fixes #330

Plumed.cmake is now treated as Plumed.inc