More fixes found trying to start up the Galera cluster

* Cannot set bind_address in my.cnf
* Missing wsrep_urls = from in front of URLs
* Needs [mysqld] group in the wsrep.cnf file
Merge pull request #3 from jaypipes/galera

More fixes found trying to start up the Galera cluster
Always default skip-federated to false with galera
Fixed problem with wsrep_sst_auth

wsrep_sst_auth value was not being set correctly
due to out-of-order issue. The secure_password
call in the galera recipe happens during converge,
whereas the attribute/default.rb creation happens
on compile stage, therefore the string produced
the password as a Chef Node Attribute instead of
string value.
Merge pull request #4 from jaypipes/galera

Fixed problem with wsrep_sst_auth