* use ES6 import / export
* UTILS: export individual utilities
* TESTS: localize TestHelper includes
BREAKING CHANGE:
* all utilities export independent functions
* library sources got ported to ES6. You must now use
a ES module bundler such as Browserify + babelify or
Webpack to consume this library (or parts of it).
This commit adds the ability to model participants from the palette.
* Empty diagrams can be used as a start for participant _AND_ process diagram
* Process diagrams can be converted to collaboration diagrams by dropping
a participant onto them
Closes#128