added reference to Two for noConflict resolve
SVG Renderer: Don't render hidden objects
merge
fixed inheritance bug
Merge pull request #111 from DieBuche/Hidden

SVG Renderer: Don't render hidden objects
Headless Qunit reference fix
Add test for group adding and removing
Rework Children

Instead of an id-indexed object, the children property is now an array.
This makes it many times faster to iterate this property and leads to actual
performance gains (see also http://jsperf.com/performance-of-array-vs-object/3)

It's not a plain array, but an array with superpowers: You can still access the contained
objects by id by doing children.ids['idOfTheObjectIDesire'].
This works, since this Array intercepts all push, splice etc. calls
and updates the ids property on every modification.

This commit also simplifies the group adding/removing methods.
Most of their work is now being handled by the generic object.replaceParent() method.
Add more tests, modify a few who accessed children by id instead of index.
Can safely add garbage to group
Make this additions/substractions an array of objects, instead of an array of idstrings.

Much faster to directly reference the object instead of searching for it in the DOM.
This is how moving was previously handled, but ideally these cases should be handled by the SVG render itself.

It might be faster though, than to access to DOM and see if the parent still has this child.
Doesn't seem to be the right thing
Restructure project a bit

Add some third-party scripts as nom modules.
Fix one test
Write custom events mechanism that avoid the frequent context switches in Backbone events

It's more bareboned but faster.. Also replace all occurences of .bind with .on, to make the distinction between Function.prototype.bind() easier.
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