Consistently use brackets rather than slashes for long lines
Parameter indentation PEP8 fixes
Fix some PEP8 inconsistancies

Fixes #202
Gets modified_time from storage, if available. Moved  common functionality for getting thumbnail and source mod times to get_modified_time in utils.py

Fixes # 180

Since storages' modified_time functions return a datetime and not a timestamp, I changed the utils.py "fromtimestamp" function, which assumed a timestamp and performed the conversion and then did timezone-aware conversion, to "make_time_zone_aware" which assumes a datetime. To deal with the fallback case where a storage doesn't implement modified_time and we use os.path directly, the new utils.get_modified_time converts the timestamp to a datetime and return that for consistency.
Don't retrieve extra fields not needed in case they are defered in
find_uncommitted_filefields
The overridden url property is no longer necessary.
The issue which the property was circumventing was fixed in django revision 600aa6679ed98d132fc378dfa205f482a58cceb1
Removed unused import.
Merge pull request #225 from kux/quoted_url

The overridden url property is not necessary

Thanks Ioan Alexandru Cucu!
Fix some tox settings
Fix a bad documentation reference to an attr
Merge branch 'retina-display' of https://github.com/jrief/easy-thumbnails

Conflicts:
	easy_thumbnails/files.py
Update settings docs to use attr docstrings
Add docs for the THUMBNAIL_HIGH_RESOLUTION setting
Update AUTHORS
Remove TODO file
Use an attribute for Thumbnailer high-resolution
1.3
Python 3 compatibility
Remove an unused import
Only check fields in update_fields (if used)

If a user issues a save with the update_fields argument (Django 1.5), it
is not necessary to check other fields in find_uncommitted_filefields,
and doing so when those fields are deferred results in extra queries.