Collapsible Trello Lists

Version 1.1.5
- WebExtensions/Firefox Compatibility.

Version 1.1.4
- More reliable method for triggering script.

Version 1.1.3:
- Improves responsiveness of background script.

Version 1.1.2:
- Use a background page to inject the script, so that it can be re-injected when a user changes boards.

Version 1.1.1:
- Fixes a bug where invalid CSS comments cause the CSS to fail loading.

Version 1.1:
- Renamed from "Collapsible Trello Columns" to "Collapsible Trello Lists" to reflect Trello's terminology.
- Added the ability for closed lists to temporarily open when cards are dropped on them. 
- Minor bugfixes

Version 1.0: Initial Commit