Leave the down_ event set

The other "up" type listeners (for touch and pointer) do not set this to null.  This event can be of use to a click listener that might want to compare the down position to the click event's position.
Provide a method to get the most recent down type event

This will allow interactions to conditionally handle later events based on the down event.
Call setRenderIntent on the feature, not the layer
Add a getFeatures method on the vector layer
Do not use a temporary layer for selected features
Removing no longer used getFeatureWithUid method
Make selectedFeaturesFilter available to other components
Do not fail on non-vector layers
add an example of how to use a WKT string in a vector source
get rid of unused markup in example
Merge pull request #1258 from bartvde/wkt

add an example of how to use a WKT string in a vector source (r=@tschaub)
Merge pull request #1252 from tschaub/expose-down

Add a getter for the most recent down event.
Protect from features without geometry
Make filter optional
Make renderIntent private and add a getter
Merge pull request #1256 from ahocevar/simplify-select

Simplify Select interaction and prepare for programmatic feature selection without interaction
Unregister for feature events when removing features
Merge pull request #1262 from tschaub/unlisten

Unregister for feature events when removing features.
Allow to set the layer style

By firing a simple CHANGE event, we can redraw the layer when
a style is assigned.
Set boolean value to HTMLInputElement.checked

See http://www.whatwg.org/specs/web-apps/current-work/multipage/the-input-element.html#attr-input-checked