Added basic Schema.org Microdata Semantics libraries

Added basic Schema.org Microdata Semantics libraries
Here you can find a Gist with documentation on how to use the package:
https://gist.github.com/PAlexcom/6038701

to load the Type classes in the CMS you must use:
JLoader::discover('Type', JPATH_LIBRARIES . '/joomla/microdata/type/');

** The Pull Request is big, but the only files I've changed/added are in libraries/joomla/microdata