Initial commit.
Added some infrastructure for internal events.

This shall come in use for further interactions between charts.
Improve tooltip rendering near edges.

Reviewer: Lisa
Compile the files.
Update unit tests and patch small issues.
Fix sorting bug.
Final (hopefully) touches to tooltips.
Merge branch 'develop' into pivot

Conflicts:
	Makefile
	polychart2.js
	polychart2.min.js
	polychart2.standalone.js