fix(core): Return promise from `handleWindowResize` method
fix(core): Return promise from `handleWindowResize` method

Current documentation says Grid.prototype.handleWindowResize returns a Promise (https://github.com/angular-ui/ui-grid/blob/fe00489/src/js/core/factories/Grid.js#L263) but in fact the internal Grid.prototype.handleWindowResize method was never returning the Grid.prototype.queueRefresh promise (https://github.com/angular-ui/ui-grid/blob/fe00489/src/js/core/factories/Grid.js#L1513). This fix allows ui-grid users to wait until the grid is correctly sized before performing certain actions (like scrolling) which require an accurately-sized grid.

dlgski/ui-grid,hahn-kev/ui-grid,alex87/ui-grid,imbalind/ui-grid,angular-ui/ng-grid-legacy,ingshtrom/ui-grid,yccteam/ui-grid,Cosium/ui-grid,angular-ui/ui-grid,dbckr/ui-grid,kamikasky/ui-grid,louwie17/ui-grid,kenwilcox/ui-grid,angular-ui/ng-grid,louwie17/ui-grid,hahn-kev/ui-grid,InteractiveIntelligence/ng-grid,InteractiveIntelligence/ng-grid,JLLeitschuh/ui-grid,imbalind/ui-grid,Cosium/ui-grid,angular-ui/ui-grid,JayHuang/ng-grid,yccteam/ui-grid,kamikasky/ui-grid,mportuga/ui-grid,Servoy/ng-grid,angular-ui/ui-grid,kamikasky/ui-grid,dpinho17/ui-grid,ingshtrom/ui-grid,mportuga/ui-grid,AgDude/ng-grid,angular-ui/ng-grid-legacy,dlgski/ui-grid,ntmuigrid/ntmuigrid,angular-ui/ng-grid,ntmuigrid/ntmuigrid,bjossi86/ui-grid,Servoy/ng-grid,YonatanKra/ui-grid,bjossi86/ui-grid,YonatanKra/ui-grid,alex87/ui-grid,Phalynx/ng-grid,dbckr/ui-grid,angular-ui/ng-grid,JLLeitschuh/ui-grid,aw2basc/ui-grid,JayHuang/ng-grid,imbalind/ui-grid,AgDude/ng-grid,alex87/ui-grid,dpinho17/ui-grid,Phalynx/ng-grid,louwie17/ui-grid,hahn-kev/ui-grid,aw2basc/ui-grid,ciccio86/ui-grid,Cosium/ui-grid,ciccio86/ui-grid,ntmuigrid/ntmuigrid,AgDude/ng-grid,dbckr/ui-grid,kenwilcox/ui-grid,bjossi86/ui-grid,dpinho17/ui-grid,yccteam/ui-grid,JayHuang/ng-grid,InteractiveIntelligence/ng-grid,JLLeitschuh/ui-grid,dlgski/ui-grid,aw2basc/ui-grid,mportuga/ui-grid,kenwilcox/ui-grid,Servoy/ng-grid,ingshtrom/ui-grid,YonatanKra/ui-grid,angular-ui/ng-grid-legacy,ciccio86/ui-grid,Phalynx/ng-grid