autorequire mysql::server in types

instead of making mysql::db have a hard dependency on mysql::server, we
now have a (soft) dependency on it through the types (mysql_user, and
mysql_database) that mysql::db uses. (n.b.: mysql_grant depends on
mysql_user so it doesn't need an explicit dependency on mysql::server)

lib/puppet/type/mysql_database.rb

@@ -4,6 +4,7 @@ Puppet::Type.newtype(:mysql_database) do
   ensurable
 
   autorequire(:file) { '/root/.my.cnf' }
+  autorequire(:class) { 'mysql::server' }
 
   newparam(:name, :namevar => true) do
     desc 'The name of the MySQL database to manage.'

lib/puppet/type/mysql_user.rb

@@ -5,6 +5,7 @@ Puppet::Type.newtype(:mysql_user) do
   ensurable
 
   autorequire(:file) { '/root/.my.cnf' }
+  autorequire(:class) { 'mysql::server' }
 
   newparam(:name, :namevar => true) do
     desc "The name of the user. This uses the 'username@hostname' or username@hostname."