convert uuid params to lower case, store only lower case uuids
fix false 'downloaded' status being returned when null hash is 'checked'
high scalability!!! using '.' instead of 'null' string
Merge branch 'master' of github.com:Jake0oo0/crafatar
Revert "Lower case UUIDs - skins/avatars"
I already commited this ;)

This reverts commit e4bdecfbb756f38a85310a205a5693b7c5055f1b.
convert keys to lower case at cache level
clean up tests
- renamed a bunch of tests to be more descriptive
- added tests for lower/upper case uuid/name
- looping over the 4 IDs (see above) instead of redefining tests

fixes #40
I guess coveralls doesn't like the 'list' reporter
get rid of typo'd package description
add twitter account to readme
Merge