[maven-release-plugin] prepare for next development iteration
Fix #5: NPE on BitmapLruCache.getFromDiskCache
Update code style + copyrights
[sample] Only use external storage for disk cache if it's usable.
[library] Throw exception if the Disk Location is not write-able.
Merge branch 'dev' of github.com:chrisbanes/Android-BitmapCache into dev
[library] Fix saving files when on a device without external storage.

The reason was that createTempFile defaults to the
 external storage. I've now added a new Builder constructor
 which takes a Context. We now use getCacheDir as the
 dir for temp files.
[library] Fix containsInDiskCache(). Closes #9
[library] Clean up CacheableBitmapDrawable.checkState()
[library] Fix #11: Adding a constructor to CacheableBitmapDrawable.java to let it implement the default (non deprecated) constructor with Bitmap parameter.
[library] Fix #13: Add an isDiskCacheEnabled() method?
[sample] Mask RejectedExecutionException. This is only the sample so fixing this isn't high on my priority list.
[library] Improve code around drawing recycled Bitmaps:

- We now disable recycling IF the Drawable isn't being displayed in a CacheableImageView
- We now record the method stack which caused the recycle call. This will help debugging problems later.
Update README
Update Manifests
[maven-release-plugin] prepare release v2.2
Merge tag 'v2.2'

[maven-release-plugin]  copy for tag v2.2