* removed old swing JEditorPane based html to png rendering due to
it's lack of support for modern css
* new implementation uses wkhtmltoimage (on prod server via wrapper
script using xvfb)
* no longer generating image on every GET request for QR, but rather
generating image when a bounty is cretaed or contract balance
changes
* images stored to DB
* comment image design updated according to UI spec
Secure Github webhooks (Fixes#18)
* Use a unique random secret for webhooks
* Validate payload signature when receiving webhook
Make enabling + disabling a repo more robust
* store repository state instead of enabled flag in DB
* atomic toggle UI button (Fixes#17)
New UX for managing repos
* group repos by owner
* look and feel according to UI spec
General improvements
* only request user's repos via Github API once per session
* fix issue with cljs code figwheel reload
* simplify app-db structure
Teemu Patja
kagel
Adrian Tiberius