added regtest

this is to test FIT_TO_TEMPLATE with TYPE=OPTIMAL and
domain decomposition (see #214)

regtest/basic/rt63c-mpi/Makefile

+include ../../scripts/test.make

regtest/basic/rt63c-mpi/align.pdb

+ATOM      1 HH31 ACE     1       0.000   0.000   0.000  1.00  0.00            
+ATOM      2 HH31 ACE     1       1.000   0.000   0.000  1.00  0.00            
+ATOM      3 HH31 ACE     1       0.000   1.000   0.000  0.50  0.00            
+ATOM      3 HH31 ACE     1       0.000   1.000   0.000  0.50  0.00            
+ATOM      8 HH31 ACE     1       2.000   3.000   4.000  0.00  1.00            
+END

regtest/basic/rt63c-mpi/config

+type=driver
+mpiprocs=2
+plumed_needs="matheval"
+arg="--plumed plumed.dat --trajectory-stride 10 --timestep 0.005 --igro helix.input.gro --dump-forces ff --dump-full-virial --dump-forces-fmt=%7.4f --debug-dd"

regtest/basic/rt63c-mpi/ddd.reference

+#! FIELDS time aaaa aaaa2 rmsd rmsd2
+ 0.000000 10.000000 10.000000 0.505276 0.505276
+ 0.050000 10.000000 10.000000 0.586683 0.586683
+ 0.100000 10.000000 10.000000 0.547766 0.547766
+ 0.150000 10.000000 10.000000 0.711042 0.711042
+ 0.200000 10.000000 10.000000 0.731741 0.731741
+ 0.250000 10.000000 10.000000 0.458276 0.458276
+ 0.300000 10.000000 10.000000 0.745021 0.745021
+ 0.350000 10.000000 10.000000 0.540015 0.540015
+ 0.400000 10.000000 10.000000 0.595892 0.595892
+ 0.450000 10.000000 10.000000 0.484320 0.484320
+ 0.500000 10.000000 10.000000 0.521010 0.521010
+ 0.550000 10.000000 10.000000 0.603059 0.603059

regtest/basic/rt63c-mpi/plumed.dat

+MOLINFO STRUCTURE=helix.pdb
+
+DUMPATOMS ATOMS=1-132 FILE=before.gro
+
+# length of first lattice vector
+cell: CELL
+aaaa: MATHEVAL ARG=cell.ax,cell.ay,cell.az FUNC=0.001*(x*x+y*y+z*z) PERIODIC=NO
+
+# rmsd with align!=displace
+rmsd: RMSD REFERENCE=align.pdb TYPE=OPTIMAL
+
+FIT_TO_TEMPLATE REFERENCE=align.pdb TYPE=OPTIMAL
+
+# length of first lattice vector
+cell2: CELL
+aaaa2: MATHEVAL ARG=cell.ax,cell.ay,cell.az FUNC=0.001*(x*x+y*y+z*z) PERIODIC=NO
+
+# rmsd with align!=displace
+p8: POSITION ATOM=8
+rmsd2: MATHEVAL ARG=p8.x,p8.y,p8.z FUNC=sqrt((x-0.2)^2+(y-0.3)^2+(z-0.4)^2) PERIODIC=NO
+
+PRINT ARG=aaaa,aaaa2,rmsd,rmsd2 FILE=ddd
+
+# here either rmsd or rmsd2 should give the same result:
+RESTRAINT ARG=rmsd2 AT=0 SLOPE=1
+# here either aaaa or aaaa2 should give the same result:
+RESTRAINT ARG=aaaa2 AT=0 SLOPE=1
+
+DUMPATOMS ATOMS=1-132 FILE=after.gro