Update tile grid option descriptions
Update tile grid option descriptions

In version 6 coordinate increase downwards.  Revise the description for "sizes" to better distinguish zoom level and overall grid extents.  Remove reference to the "widths" options which was deprecated over 4 years ago.
ahocevar/openlayers,oterral/ol3,geekdenz/ol3,adube/ol3,stweil/ol3,ahocevar/ol3,ahocevar/openlayers,ahocevar/ol3,bjornharrtell/ol3,stweil/openlayers,geekdenz/openlayers,adube/ol3,openlayers/openlayers,stweil/openlayers,ahocevar/ol3,ahocevar/ol3,bjornharrtell/ol3,geekdenz/openlayers,geekdenz/openlayers,openlayers/openlayers,openlayers/openlayers,stweil/ol3,geekdenz/ol3,ahocevar/openlayers,bjornharrtell/ol3,geekdenz/ol3,oterral/ol3,stweil/openlayers,stweil/ol3,geekdenz/ol3,stweil/ol3,adube/ol3,oterral/ol3