Remove unused CSS classes

The classes ol-layers, ol-layer-image, and ol-layer-tile are not used.
Add spiral to Madrid animation example
Cosmetic clean-ups
Merge pull request #669 from twpayne/more-animations

Minor changes to the animation example
Don't escape HTML characters in shader generation

This tells Mustache not to escape <, >, &, and " characters.
Merge pull request #670 from twpayne/fix-glsl-escaping

Don't escape HTML characters in shader generation
Export ol.Map.updateSize
Merge pull request #672 from fredj/export-update-size

Export ol.Map.updateSize
Merge pull request #666 from twpayne/remove-unused-css-classes

Remove unused CSS classes
Redefine ol.Pixel to be Array.<number>