Implement mouse over radar for selecting vertices. In progress #138.
Need data series in radar's hit. Work for #138
Mouse tracking in radar sample added to show the new feature
Make DOM interaction jQuery compatible.

Fixes #148.
Fix missing semis.
Added remove method to DOM library.
Do not empty container div and cleanup markup when done.
Configurable container for mouse tracker for #121.
Built.
Merge branch 'master' into 121-mouse-track-container
Built.
Merge branch 'master' of https://github.com/HumbleSoftware/Flotr2 into radar-mouseover
Fix JSHint extra commas
Use 2 spaces for tabs as in the rest of the code
Fix the aligntment when centered.
Add detection of event on mouse track div.
Built.

Fix for flashing tracker.
Fix for alignment.
Added CONTRIBUTING.md
Merge branch 'radar-mouseover' of https://github.com/Bitergia/Flotr2 into radar-mouseover

Conflicts:
	flotr2.min.js

Resolved with rebuild.
Make margin explicitly configurable per-axis.

For #188.