- cleanup of tabbed code editor:
 * split out css into seperate file
 * moved demo items (list of documents) to demo.html
 * added handling of change of documents list
- modified usco-editor to use tabbed editor instead of simple code editor (work in progress)
- css/styling improvements
- started adding "pub/sub", messages handling
- added new element : usco-base-ui which acts as main wrapper/ui
(end goal is to be roughly the same as current coffeescad ui)
 * added base files & demo
 * experimenting with newer polymer elements
- updated bower dependencies