vinc/mongoid_token — pull request #1 by vinc (2014-06-15 10:18:06+00:00)
Title: Add lowercase and uppercase alphanumeric generators

I wanted to generate lowercase alphanumeric tokens so I modified the Generator module to do that and the same for uppercase. I added `%a` and `%A` quite arbitrary, maybe there's a better letter.

I'm using the mongoid-4 branch and the code contains a new helper function `rand_string_from_chars` so my PR is based on this branch instead of master.