Improved the build matrix.
Merge pull request #19 from thedrow/patch-2

Improved the build matrix.
Minor clarification to readme

Add import line to first settings example.
Merge pull request #20 from meshy/patch-5

Minor clarification to readme
URL schema standardized

Uses standard url schema for sockets, querystring to allow for cache
arguments and an optional redis database url component.

Related to ghickman/django-cache-url#16 and ghickman/django-cache-url#14
Update redis url format to match convention.

The database number is specified in the path to match how other DSN's specify
database names.