Update class diagrams to handle comments

updated regex in parser to correctly handle comments in class diagrams.  Also updated flowchart parser to remove unused elements for comments, as well as modifying the regex to match

src/diagrams/class/parser/classDiagram.jison

@@ -9,7 +9,7 @@
 %x string struct
 
 %%
-\%\%[^\n]*            /* do nothing */
+\%\%[^\n]*\n*           /* do nothing */
 \n+                   return 'NEWLINE';
 \s+                     /* skip whitespace */
 "classDiagram"          return 'CLASS_DIAGRAM';