Factor out common code and test

The findInterimTiles method was used in three renderers.  This change makes it available on the tile source and adds some basic tests.
Fix return from findLoadedTiles

Previously, the findInterimTiles method was returning undefined if the min x/y coord for a tile range was already in the lookup.  The return says it indicates whether all tiles for the given z are loaded.  This change corrects the return.

This change also reveals a misunderstanding of the tile range returned by `getTileRangeForExtentAndZ`.  The previous findInterimTiles method was treating max values as inclusive.  This is intuitive.  It looks like the method returns a range where max values are exclusive.
Passing tests
Merge branch 'master' of github.com:openlayers/ol3 into interim-tiles
Several fixes to the WMS Capabilities parser

Make sure the object structure returned is not mangled by Closure

Do not use closure XHR or JSON in the example

Use Jasmine's async support in the test cases

Get rid of some backwards compatibility now that we have a fresh start
Fewer tiles to be considered fully loaded

With 797dba2cdbabd8fa0a78c32a7b3bfcdbff29eea8 we no longer have to load excess tiles to consider an extent fully loaded.
Accept custom isLoaded method in findLoadedTiles method
View needs to call constructor on super
Removing unnecessary overhead
Using hasOwnProperty is better for user keys on objects we control
Key in obj check not appropriate for user supplied keys
Properties set with set should not be accessed with bracket
Using a dedicated object for value storage

Without this, we are limited in the key names that we can accept from users.  And because of compiler renaming, we don't know ahead of time what the limitations are (e.g. the key 'a' may clobber the 'set' method).
Add method for getting keys
Update readme Add examples section
Merge pull request #204 from bartvde/wmscapsfixes

fixes for the WMS capabilities parser (r=@elemoine)
Merge pull request #206 from tschaub/interim-tiles

Share common code to find loaded tiles
Merge pull request #220 from elemoine/readme

Update readme Add examples section
Update Run examples locally readme section
Windows users should run build serve