Care with transform

Since the transform method takes an arbitrary transform function, new coordinates may not be ordered in the same way as the originals.
Checked with third-party tool
Punctuated
Merge pull request #153 from tschaub/extent

Care with transform
Fix typo
Merge pull request #155 from elemoine/typo

Fix typo in a typedef
Remove ref to userProjection

The wms-custom-proj example sets a userProjection in the map while userProjection is gone for now. It was removed in 927cffb2.
Merge pull request #156 from elemoine/examplefix

Remove ref to userProjection
Add working UI for a zoomslider control.

Currently this is not fully functional, as some APIs in the ol.Map aren't
currently available.
More work on the zoomslider.