Merge branch 'v2.3' into v2.4

CHANGES/v2.3.md

@@ -220,5 +220,6 @@ For developers:
 
 For developers:
 - Doxygen on travis-ci has been updated to 1.8.14
+- `make clean` now correctly removes the `src/lib/plumed` executable.
 
 

src/lib/Makefile

@@ -518,8 +518,7 @@ endif
 .PHONY: clean dirslinks
 clean:
 	rm -f $(CLEANLIST)
-	rm -f $(PLUMED_MAIN_STATIC) $(PLUMED_MAIN_SHARED) $(PLUMED_MAIN_RUNTIME)
-	rm -f Plumed.inc* plumed-* Plumed.cmake*
+	rm -f plumed Plumed.inc* plumed-* Plumed.cmake*
 # this is not necessary, I leave it here to remove spurious plumed.vim files generated with
 # the first version of plumed.vim syntax file:
 	rm -f plumed.vim