Added MULTI_RMSD as an alias to MULTI-RMSD

See #435

src/colvar/MultiRMSD.cpp

@@ -148,6 +148,28 @@ END
 
 PLUMED_REGISTER_ACTION(MultiRMSD,"MULTI-RMSD")
 
+//+PLUMEDOC DCOLVAR MULTI_RMSD
+/*
+An alias to the \ref MULTI-RMSD function.
+
+\par Examples
+
+Just replace \ref MULTI-RMSD with \ref MULTI_RMSD
+
+\plumedfile
+MULTI_RMSD REFERENCE=file.pdb TYPE=MULTI-DRMSD
+\endplumedfile
+
+*/
+//+ENDPLUMEDOC
+
+class Multi_RMSD :
+  public MultiRMSD {
+};
+
+PLUMED_REGISTER_ACTION(MultiRMSD,"MULTI_RMSD")
+
+
 void MultiRMSD::registerKeywords(Keywords& keys) {
   Colvar::registerKeywords(keys);
   keys.add("compulsory","REFERENCE","a file in pdb format containing the reference structure and the atoms involved in the CV.");