Bumblebee-status

Mostly a bugfix release

**New module**
* amixer sound levels (thanks to zetxx)

**Bugfixes**
* More accurate disk usage calculation for the "disk" module (thanks to yashar-sb-sb)
* Improved pacman module (separate thread for background querying) (thanks to yashar-sb-sb)
* Fixed custom update interval

New modules in this release:
* gpmdp (by paxy97): Add information and controls for the [Google Play Music Desktop Player](https://www.googleplaymusicdesktopplayer.com/)
* weather (by paxy97): Show temperature retrieved from [OpenWeatherMap](https://openweathermap.org/), with support for automatic location detection
* kernel (by pierre87): Show current Linux kernel version
* redshift: Show current status (day/night + color temperature) for [Redshift](http://jonls.dk/redshift/)

Misc:
* Added support for Python 3.6
* Minor code improvements (particularly, in the nic module)

Fixed bug in v1.1.0 in module "pulseaudio": Volume & status detection broken with multiple devices

New features:
- new module "pacman" (contributed by Pseudonick47): Show pending pacman updates
- new module "xrandr": Show, disable and enable attached displays
- new module "layout": Show and cycle keyboard layouts (contributed by Pseudonick47)
- new parameter for "nic": Configure list of excluded interfaces
- themes: Themes can now use (and define) icon sets

Other:
- Major rewrite of the backend code (should be more stable and extensible now)
- Full Python3 support

1st official release