Clone e.srcEvent when processing hold events to allow src to stay alive in IE, since it otherwise might be put into zombie mode after returning to the event loop.
Fix e.which handling for the odd case of IE10 running in IE8 mode with <meta http-equiv="X-UA-Compatible" content="IE=edge,chrome=1"> set in the document. That was enabling PointerEvents, but leaving the system in IE8 mode for most everything else.

Enyo-DCO-1.1-Signed-Off-By: Ben Combee (ben.combee@lge.com)
Update PlatformSample.js with fallback for window width/height for IE8

Enyo-DCO-1.1-Signed-Off-By: Ben Combee (ben.combee@lge.com)
Rework enyo.dom,getComputedStyle to have a better polyfill for IE8 that handles converting from padding-top to paddingTop.
Adjust enyo.dom.getComputedBoxValue to deal with "auto" as a margin value by converting to 0 instead of NaN.  This was seen loading sampler in IE8.

Enyo-DCO-1.1-Signed-Off-By: Ben Combee (ben.combee@lge.com)
Merge pull request #263 from enyojs/ie8-fixes

Ie8 fixes