user module: return public SSH key

Return public SSH key if the user module is called with generate_ssh_key=yes.
Since "user" doesn't overwrite files, this also allows querying of existing
public keys.

Used in playbooks together with the "register" keyword, the returned key can be
passed to the "authorized_key" module allowing easy setup of SSH public key
authentication between remote hosts.
Add module postgresql_privs

This Module allows to manage privileges on PostgreSQL database objects
(currently: tables, sequences, functions, databases, schemas, languages and
tablespaces) as well as group role memberships.

It is basically a wrapper around most of the functionality of PostgreSQL's
GRANT and REVOKE statements with additional detection of changes and support
for dry-runs (check-mode).

postgresql_privs should work with PostgreSQL 8.4 and above. Python Module
psycopg2 is required on the remote host.
Merge pull request #2673 from b6d/user-module-extension

user module: return public SSH key
Merge pull request #2676 from b6d/postgresql_privs-module-proposal2

Proposal for a module to manage PostgreSQL privileges (2)
Working on the FAQ.