Merge pull request #1140 from jcb91/htmltools

[js_highlight.py] move into nbconvert_support, specify exception type

Author: jcb91

src/jupyter_contrib_nbextensions/nbextensions/htmltools/js_highlight.py renamed to src/jupyter_contrib_nbextensions/nbconvert_support/js_highlight.py

@@ -21,7 +21,7 @@
 
 try:
     from html.parser import HTMLParser  # py3
-except:
+except ImportError:
     from HTMLParser import HTMLParser  # py2