WMS-1119:Data is lost on resizing columns in grid when pagination is present
Retain Sort info on rebuild of grid columns.
Merge branch '2.x' of https://github.com/vinay-k/ng-grid into 2.x

Conflicts:
	build/ng-grid.js
Merge pull request #6 from vinay-k/2.x

Retain Sort info on rebuild of grid columns.