VBENCH: rename parser.py to parser_vb.py

Author: y-p

vb_suite/parser.py renamed to vb_suite/parser_vb.py

@@ -17,12 +17,12 @@
            'miscellaneous',
            'panel_ctor',
            'packers',
-           'parser',
+           'parser_vb',
            'plotting',
            'reindex',
            'replace',
            'sparse',
-           'strings',           
+           'strings',
            'reshape',
            'stat_ops',
            'timeseries',