Merge pull request #525 from TravisPaul/master

Add object_straightening module to README.md
Specify that loadSVGFromURL uses XHR and conforms to SOP
Fire event 'removed' on object level

There is ```obj.fire('added')``` but not ```obj.fire('removed')```.
Merge pull request #528 from Kienz/patch-3

Fire event 'removed' on object level
rendering canvas on node.js - fixed issue with segfault occuring when downloading an image that comes from https (secure) url
Activate clicked object if group selection is cleared

If group selection is cleared and pointer clicked other object 
=> activate this object.

See issue #506
Don't set activeObject if clicked on activeGroup

canvas._activeGroup should be null if clicked on activeGroup. 
Only set activeObject if target !== activeGroup.
Merge pull request #534 from Kienz/patch-1

Activate clicked object if group selection is cleared
Fix reset shadow of fabric brushes
The jsdoc params for fabric.Image.clone() were out of order, making
the jsdoc API reference for this method at

    http://fabricjs.com/docs/symbols/fabric.Image.html

display an incorrect method summary (with the order of propertiesToInclude
and callback swapped).
Add link to Event.js library

Add link to Event.js github repository to gestures module
Merge pull request #539 from taherh/master

Minor jsdoc comment fix for fabric.Image.clone()
Merge pull request #537 from Kienz/shadowBrush

Fix reset shadow of fabric brushes
Merge pull request #540 from Kienz/patch-2

Add link to Event.js library
Merge pull request #531 from shiloa/master

Fix crash (segfault) on node.js if canvas loads images with secure url (https://...)
Document strokeDashArray on fabric.Rect
Support stroke on image instances. Closes #536
Fix positioning of line and image instances when part of a group
[BACK_INCOMPAT] fabric.Text#strokeStyle -> stroke, for consistency with other objects. Closes #535
Preserve group reference on objects in group after adding/removing some object from group. Closes #533