chef_wm_password supports both EC and OSC password data schemas

* Add support for EC/OSC sha1+bcrypt types
* support forlegacy sha1+salt types
* upgrade function
* tests for the above
* added a password test data generator rb file

ping @opscode/server-team 
Note here that a search through all repos didn't show migrate_sha1 being used - its only apparent use was for generating test data.