Added pmprosm_getUserByCodeID and pmprosm_getSponsor functions.
* Added pmprosm_getUserByCodeID and pmprosm_getSponsor functions.
* Added the discount code and code URLs to the sponsored members checkout confirmation email.
* Added ability for a sponsored code to work on multiple levels. Just pass an array for the 'sponsored_level_id' value in the pmprosm_sponsored_account_levels global.
Merge branch 'master' of github.com:strangerstudios/pmpro-sponsored-members

Conflicts:
	pmpro-sponsored-members.php