Removing table cells and replacing with Bootstrap grid on new layer form. Altering all dropdown lists to Bootstrap style. Adding local arrays for new dropdowns in layers.js.
Merging pull request #679 from RobertDenis/layer-table-bootstrap-grid.

Conflicts:
	geoserver/webapp/app/app.less
	geoserver/webapp/app/layers/addnewlayer-modal.tpl.html

Closes #679.