Clarify keyboard events and focus in docs
Vector renderer uses the layer revision
Export ol.Observable#dispatchChangeEvent
Add comments for setStyleFunction
Add comments for the canvasFunction option
Fix the touch interactions

This fixes a bug introduced by https://github.com/openlayers/ol3/commit/318fc6815901380bdc7c9d1921cb5a9cc1e6e2ff.  Thanks @gjn for reporting the problem.
Calculate pixelRatio before using it

This fixes a regression introduced by https://github.com/openlayers/ol3/commit/646dd18 where the device pixel ratio was used to determine the tile size even though serverType was not defined for the source.
Merge pull request #1619 from elemoine/touch-interaction-fix

Fix the touch interactions
Add export for ol.proj.METERS_PER_UNIT
Improve use of View2D in ol.control.ZoomToExtent
Factor out common variable in ol.dom.Input
Improve type checking in ol.events.condition.targetNotEditable
Improve type checking in ol.format.Polyline.decodeDeltas
Improve type checking in ol.geom.Circle#setCenterAndRadius
Don't attempt to use Uint8Array in ol.geom.simplify.douglasPeucker
Fix option property in ol.interaction.KeyboardPan
Improve type checking in ol.interaction.Select
Improve type checking in ol.Map
Use ol.ENABLE_* to help Compiler eliminate unreachable code
Improve type checking in ol.Object#bindTo