* 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 makes use of the provider concept introduced
in diagram-js. The replace menu entries are now created
in the replace menu provider. This separates BpmnReplace
from the entry creation in the popup menu.
Closes#428