Change error system. urllib2 substituted urllib
Add resources.py
Renamed module
site_list move to resources.py
Added JSON exception
Changes in PybooruError
Added more doc
Added more documentation for functions
Change _site_name error
_url_validator changed and simplified
Change __init__, parameters and  attributes
Added more documentation
All print substituted for raise
Small fix
Merge pull request #2 from LuqueDaniel/master

Update branch develop
Removed attribute trash
Removed Nekobooru site, site is not available
More changes in __init__
Change version number
Added dict with API base URLs