added an importer.py

for importing bookmarks n stuff

currently supports chromium bookmarks

usage:
in chromium: export your bookmarks to html file (bookmark manager)
./importer.py chromium bookmarks_10_11_14.html >> ~/.config/qutebrowser/quickmarks

** waiting for the perfectionist™ to judge me hard **
;-)
With python3, you should be able to use the built-in `open()` with `encoding=...` instead of `codecs.open`.