Update to Polymer 2.0

[moebiusmania]

Update code syntax and structure to match the Polymer 2.0 syntax, when it will be ready!

• Document on how to write Polymer 2.0 components
• Make them ES2015 module compliants
• Try out the upgrade tool (when it will be released)

After this update we will need to specify the last tag of this repo that will compatible with Polymer 1.x

[moebiusmania]

Polymer 2 has reached the Release Candidate status, so I've created a test branch ;)

[moebiusmania]

All future development of this components library will be done on a new organization and various repositories inside of it.

https://github.com/orkestra-elements