put loading of data source dependency in initialize method, per puppetlabs specs
cleanup conflicting license
use Backend.merge_answer per puppetlabs specs
https://docs.puppetlabs.com/hiera/1/custom_backends.html
adds useful debug and warn messages if redis cannot be loaded
change error message so it is less confusing when repeated
Merge pull request #1 from rubyisbeautiful/1.0.4

1.0.4