OpenLayers: update to 2.13-rc5

Based on 91f9c19a (Tobias' private OL clone, 2.13 branch), which has
the google layer patches of ahocevar applied on 1cf69634cf (OL 2.13).
map.js: add TileManager to make the map more responsive on mobile devices
map.js: set transition effect to 'map-resize' on map overlays
map.js: enable fallThrough which is needed by the GraphicLayerSwitcher
OpenLayers.css: include changes from 2.13dev
assets/bundles: use closure for openlayers bundle
map.js: disable animated zoom
Merge pull request #58 from TobiasLohner/ol2.13

Updated OpenLayers to 2.13dev