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
fixed a typo
Improve crash log handling because of single-instance.
Never delete crash log file.

We also want to log to the crash log when segfaults happen during exit.
Remove unused faulthandler import.
Save lineparser even if there is no data.
Remove cookies when permissions->cookies-store was changed.

Fixes #116.
Add a simple wrapper around Qt's app.exec_().

This improves faulthandler tracebacks.
Split quickmarks correctly (from the right).

This was discovered in #189.
Merge branch 'master' of https://github.com/claudehohl/qutebrowser into claudehohl-master
importer: Use choices=... for argparse
importer: Whitespace cleanup
importer: Use built-in open
importer: Import cleanup
importer: Clean up string formatting
importer: Add docstrings.
importer: Fix printing of usage
importer: Add module docstring
importer: Add help message about Chromium
Merge branch 'claudehohl-master' (bookmarks importer)