feat #745 enable `getComputedStyle` for IE9+

Close #745.
refactor some positioning/viewport calculations

1) don't recalculate the viewport size in `onViewportResized` in Dialog,
take it from event data
2) round to full pixels in `utils.Dom.calculatePosition`
(`getBoundingClientRect` returns floats)

Close #677.
feat #714 custom padding for the `pad` modifier

Now the `pad` modifier accepts third parameter which is the padding
string. By default it's `&nbsp;` if not provided.

Close #714. Close #724.
fix #749 enable VisualFocusTest in IE8
fix #750 aria.utils.json.JsonSerializer wrongly escaped the keys in some cases
fix #752 Optimisation on the JsonSerializer, after #750
fix #751 pixel-percentage conversions broken

Conversions between pixels and percents were working only in IE8-
due to a mistake in 107507a30d0407e46bcbf6dea3cf31ee28c43928.
feat #718 option to use `referenceId` in `@touch:Dialog`

Close #718. Close #726.
fix #713 Slider widgets improvement (touch library)

Close #715.
feat #747 Added and refactored easing functions for animations
fix #740 touch button test case on ie7
fix #720 More positioning options for the Touch:Dialog widget

Close #733
Fix #730 Validation errors in page engine instances when navigating between pages with submodules
fix #672 DefaultAppender error display on Chrome

Changed error method of aria.core.log.DefaultAppender to explicitly log
the name and message of the original js error, if provided.

Close #673
fix #758 test.aria.html.textinput.autoselect.AutoselectTestCase fails on IE 10
fix #759 EscapeOnModalAndNonModalTest fail in IE7
fix #761 test.aria.widgets.icon.IconTest failing on IE10

This commit fixes test.aria.widgets.icon.IconTest which started
failing in d483056c6edf8064781d069101fdca40b874ac15 because the
type of absolutePosition.top in the popup configuration changed
from json:Float to json:Integer (when the config bean was moved
from aria.utils.DomBeans to aria.popups.Beans).

This commit restores json:Float in
aria.popups.Beans.AbsolutePositionConfig.
fix #763 Typo and parameter issue in error message in BindableWidget
v1.4.11
fix #766 IE8 issue when displaying a popup.

This fix has two parts, firstly it will resolve an issue
for animations in IE8 when displaying a popup, and secondly
it refactors a bit the way animations are used, there is now
a getter to load animations when they are actually needed,
and not for all popups as was previously the case (this will
help to improve performance particularly for IE8).