Tag views with ImagePresenters in constructor

This should be safe since we're using tag with
an id and it eliminates one extra step required
to use ImagePresenters.
Comment updates and fixes for various warnings
Add defaults for loaders using Glide singleton
Cleaner and more efficient Glide api

Reduces the # of extraneous object allocations by
lazily creating objects only if a new presenter is
needed. Adds some metadata to view tags to
determine whether or not options for a view are
the same, so an existing presenter can be used
or have changed, so a new presenter has to be
created
DrawableLoader -> ResourceLoader
Remove generics from ImagePresenterCoordinator

No reason why it can't coordinate presenters for
different types of models
Remove misleading constructors from RecycleableBIS
Call cb in background in VolleyStreamLoader

This means our code in the cb will run on a
background thread. Though all we do is post to a
thread pool, this change means we don't need to
acquire that lock on the main thread.
Increase Bitmap compression in flickr sample

Increases # of images that will fit into cache
Updated readme
ImageSetCallback -> ImageReadyCallback
Add an error placeholder
Allow VolleyModelLoader to set a retry policy
Handle views with wrap_content set in Glide
Refactor duplicate code in ImageResizer to classes
Change default tag to Glide
Mildly reduce # of posts to bg thread per resize
Add retries to flickr search in sample project
Cache inefficient Url creation per photo

String.format is rather terrible
Code cleanup in ImageManager