remove need to pass root_password twice

[jburnham]

in order for the root_password to be set in the /root/.my.cnf and also manage it with mysql_user, you have to pass root_password to mysql_server and also add root_password to the override_options hash. Why not merge in the root_password parameter into the options hash as a third hash, something like:

$root_pw_hash = { root_password => $root_password }
$options = mysql_deepmerge($mysql::params::default_options, $override_options, $root_pw_hash)

This way in mysql::server::root_password template it can continue to lookup the root_password from the options hash. You would also change the if statement to be like

if $mysql::server::options['root_password'] != 'UNSET' {

[jburnham]

I can do this as a PR once you merge in #282

[jburnham]

fixed in #288