`display` skipping & one-time callback execution

You can now skip having the UI Pack effect change animating elements' `display` property by passing in `display: null` as an option into the sequence call.

Further, callback behavior now mimics that of standard Velocity animations: `begin` and `complete` are only fired once, regardless of how many elements were passed into the Velocity call. (Prior to now, they were firing once per element in the call.)

Thank you to @devertnet and @bendiksolheim.
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SVG Animation Support

Closes #74. See http://velocityjs.org/#svg for info.
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Comment Modifications

No code was changed in this release. Only comments were modified.

Closes #133: Constrain comments' line length to better match GitHub's
code viewport. Thanks for the suggestion, @nikola.
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fix #134 unhandled console.log in IE
3D SVG Support

Added support for 3D CSS transforms for SVG elements (for all browsers
but IE and Android non-Chrome, where it’s not possible). Closes #137.
(Thanks, @jackrugile.)

Suppressed IE8 console log output. Closes #134. Closes #139.

Removed trailing whitespace.
Merge branch 'pr/139'
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Version Updates
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Implemented Promises support