Merge pull request #1458 from Intermedix/bug-insert-valueExtent

Fix bug in ol.structs.RBush#update
Add a ol.source.ImageStatic example
Merge pull request #1374 from fredj/static-image-example

Add a ol.source.ImageStatic example
Merge branch 'master' into feat-ie-compat-reint
Fix IE7/8 selection issue when no layers are rendered
Merge branch 'dev-ie-layer-opacity' into feat-ie-compat-reint