Initial work on user/source/grant/revoke management
More work on security
Some initial work on GRANT/REVOKE
Fix  a bug with wildcards
Implement REVOKE and fix some bugs
Support for certificate authentication
Implement initial security context renewal based on a global epoch
Add pbkdf2 as a dep
Initial pass at generating a pbkdf2 pass
Fix hmac algorithm
Move password auth into its own module
Add ability to register to a proplist
Support dynamically registered auth backends
Updates to pw_auth and riak_core_security modules
Remove unneeded case statement
Logging the plaintext password would be bad
Remove extra newline
WIP rebase on top of cluster metadata
More WIP cluster metadata work