Updating to latest ol3 version

https://github.com/openlayers/ol3/commit/ad1f255211aeadc522ebb9edbfcf27dfc4a89015
Fix rebase after offline merge, ol3 update:
https://github.com/openlayers/ol3/commit/5416badde15d8f756a5ea9b478594cb140834e98
Merge pull request #1543 from geoadmin/gjn_updatepol3

Updating to latest ol3 version