Rename and refactor database to mysql_database.

Add collate as a new managable parameter, and extend self.instances to
add in all parameters when checking existing databases.  It also adds
self.prefetch in order to speed up Puppet runs.

Provider is also switched to using mk_resource_methods to generate
all the resource readers, and exists? and other methods now use the
property_hash where appropriate.

Tests rewritten to handle changes and extend code coverage.
Rename and refactor database_user to mysql_user.

This work adds max_connections_per_hour, max_queries_per_hour, and
max_updates_per_hour support to the provider and extends self.instances to add
in the new parameters when checking existing users.  It also adds
self.prefetch in order to speed up Puppet runs.

Provider is also switched to using mk_resource_methods to generate
all the resource readers, and exists? and other methods now use the
property_hash where appropriate.

Tests rewritten to handle changes and extend code coverage.
Use new provider names in manifests.

Modify manifests and tests to handle the renamed providers.
Rework tests for mysql_password to extend coverage.
Add simplecov support in order to generate test coverage.
Add rspec-system test for mysql_user.