Add 'sortable' CSS class to sortable headers (#514).
Pass the right row to 'asyncPostRender' function (#505).
Added distance to prevent unintended reordering

Added a small distance delay on the sortable to prevent users from unintended
triggering of the reordering. (Happens all the time i'm using slickgrid).
i.e. the users tries to sort the column but fails since his mouse was still
on the move a little bit and 1px is enough to trigger reordeing here.
Please try, it still feels very responsive.
Replace 'hover' deprecated pseudo-event

'hover' pseudo-event has been deprecated in jQuery 1.9.0,
use of 'mouseenter' and 'mouseleave' instead.
Changed distance value
Fix #520 - dropstart event not firing
Use of navigator.userAgent instead of $.browser

$.browser object has been removed from jQuery 1.9.0
Added distance for dragging rows

Added distance to prevent users from unintended dragging of rows.
Shift+arrow keys support for selection
Use a URL instead of a path for the wiki link in the README

GitHub currently transforms the path into a blob-style URL for the wiki, which is a 404
Changes according Pull request #534

numeric keycodes
{} for ifs
Add multi-level grouping to DataView.
Based on the original pull request (https://github.com/mleibman/SlickGrid/pull/522) by ghiscoding.

Deprecated DataVIew APIs (will continue to work):
- .groupBy()
- .setAggregators()

New DataView APIs:
- .getGrouping()
- .setGrouping(groupingInfo)
- .setGrouping([groupingInfo1, groupingInfo2, ...])
- .collapseAllGroups()
- .collapseAllGroups(level)
- .expandAllGroups()
- .expandAllGroups(level)
- .collapseGroup(groupingKey)
- .collapseGroup(level1value, level2value, ...)
- .expandGroup(groupingKey)
- .expandGroup(level1value, level2value, ...)

Grouping info options (for use in .setGrouping() calls):
- getter
- formatter
- comparer
- aggregators
- aggregateCollapsed
- aggregateChildGroups
- collapsed

New Group fields:
- level
- groups
- groupingKey

Also fixed 0-handling in default aggregators.