Add a size based pool for api 19+

Fixes #34
Fix unclosed OutputStream in DiskLruCacheWrapper (reported by StrictMode).
Be slightly more paranoid about closing os
Update volley
Assert if tag is set on target ImageView

Fixes #62
Don't import * and rename thread in ImageManager
Bump version for incremental release
Update read me
Filter and dither bitmaps when transforming them
Allow manual overrides of bitmap compress format
Save bitmaps without alpha as jpegs
Merge pull request #64 from sjudd/allow_force_compress_format

Allow overriding default compress format
Don't use a special downsampler in ImageManager

It doesn't work for non exact sizing.
Merge branch 'fix_problem_decoding_from_disk_cache'
Make SafeKeyGenerator thread safe.
Fix bitmaps too large for memory cache being added to pool too soon.
Increase the default cache size and default to internal cache dir.
Use small memory cache and large bitmap pool on new and non low ram devices.
Decrease the default number of threads glide uses to resize images.
Add debug logging for exceptions loading images.