Udiskie

- go async (with self-made async module for now, until gbulb becomes ready)
- specify GTK/Notify versions to be imported (hence fix warnings and a problem
for the tray icon resulting from accidentally importing GTK2)
- add optional password caching

- officially deprecate udisks1
- officially deprecate python2 (want python >= 3.5)
- fix startup crash on py2
- fix exception when inserting LUKS device if ``--password-prompt`` or udisks1 is used
- fix minor problem with zsh autocompletion

- fix attribute error when using options in udiskie-mount (159)
- fix tray in appindicator mode (156)
- possibly fix non-deterministic bugs (due to garbage collection) by keeping
global reference to all active asyncs

- handle XDG_CONFIG_HOME variable without external pyxdg dependency
- silence warning when using AppIndicator
- make ``--appindicator`` sufficient to show icon (previously additionally
required ``--tray``)
- improve wording in password dialog "Remember" -> "Cache"
- make some of the logging more concise
- fix recursive adding/removing of some child devices:
- fix incorrect root device detection for devices without Drive property
(e.g. children of loop devices)
- fix ``--detach`` option when applied to partitions of loop devices

- add russian translations (thanks mr-GreyWolf)
- fixed deprecation warnings in setup.py (thanks sealj553)

- log INFO events to STDOUT (112)
- fix exception in notifications when action is not available. This concerns
the retry button in the ``job_failed`` notification, as well as the browse
action in the ``device_mounted`` notification (117)
- don't show 'browse' action in tray menu if unavailable