Designate submodule API class for static classes

Module APIs are submodule classes, this one is now designated for static
classes, to be used as: self::API('submodule', 'method', 'param');
New SubModule Object class API

A new submodule API that can be used by a module to use submodule class
objects. Used as: $this->Object('submodule', 'param')->method or
variable.  The 'param' is optional and is passed to the class construct.
Plugins Get submodule update