Fix clicking the bear on mobile

closes #469
Merge pull request #475 from glowing-bear/fix-bear-click

Fix clicking the bear on mobile
Create dark theme by extracting theme settings from glowingbear.css

* Remove style.css as those values should be themable as well.
* Update urls in index.html to link to dark theme by default
Add light theme
light-theme: darken most colors by 50% and add it to theme manager
light theme: improve colours

* make the background lighter
* set highlight colour to something readable
* improve readability of default grey colours
* make default text color readable
* fix some base colours
style option control in light theme
fix gap between input and content
Fix bug with background color bleeding through
Merge pull request #434 from glowing-bear/design-light-theme

Design light theme
Make buttons unselectable

This improves copying and pasting quite a lot
Support narrowing buffer selection with Alt+0-9 after using Alt+g or when onlyUnread is enabled, and show numeric overlays for Alt+0-9 keys on the buffers
Quick keys disappear only after releasing alt key

Other changes:
- 0.2s delay so they don't appear when pressing Alt+A etc
- don't appear when other modifier keys are pressed
Merge pull request #482 from glowing-bear/make-buttons-unselectable

Make buttons unselectable
some scrolling updates
Fix bufferlist spacing on mobile

The current version is much too tight to hit, and for some reason I only
fixed it in the cordova branch. This should go into master, though.
Restore space at the bottom of buffer lines
Merge pull request #486 from glowing-bear/fix-buffer-bottom

Restore space at the bottom of buffer lines
fix $apply exception on showSidebar
make pageup key trigger fetch more lines