Prototype rewrite as role
Added more tests
Support a list of failover classes
Added some POD
Updated .gitignore [ci skip]
Tweaked Dist::Zilla config
Added an example
Default err_arg is called 'error'
Removed comment
Removed CHECKARGS method

Checking the arguments first, and then calling the constructor with
error checking was roughly 8% slower than just calling the constructor
with error checking.
Some minor optimizations
Added more tests
Tweak for Travis config due to File::Find::Rule issue
Merge pull request #1 from robrwo/rrwo/rewrite-as-role

Rewrite this to use a Role