Added install_name_tool on mac

This fixes the hardcoded path on dylibs

src/lib/Makefile

@@ -189,6 +189,10 @@ endif
 ifdef SOEXT
 	cp install/libplumed.$(SOEXT) "$(DESTDIR)$(libdir)/lib$(program_name).$(SOEXT)"
 	cp install/libplumedKernel.$(SOEXT) "$(DESTDIR)$(libdir)/lib$(program_name)Kernel.$(SOEXT)"
+ifeq ($(SOEXT),dylib)
+	install_name_tool -id "$(libdir)/lib$(program_name).$(SOEXT)" "$(DESTDIR)$(libdir)/lib$(program_name).$(SOEXT)"
+	install_name_tool -id "$(libdir)/lib$(program_name)Kernel.$(SOEXT)" "$(DESTDIR)$(libdir)/lib$(program_name)Kernel.$(SOEXT)"
+endif
 endif
 # modulefile
 	cp install/modulefile "$(DESTDIR)$(libdir)/$(program_name)/modulefile"