ez_setup: Update to 5.8
run_checks: Add PWD to os.path.

Without this change, running checkers when not running unittests failed,
because qutebrowser couldn't be imported.
Merge branch 'master' of ssh://lupin/qutebrowser
pylint: Add checker for open() without encoding.
Add explicit encoding to open() calls.
Update TODO.
pylint_checkers: Don't check binary open in openencoding.
Make editor config configurable
Fix ignore_case for searching.
Fix logfilter
Merge branch 'master' of ssh://lupin/qutebrowser