enable the use of all ( i think ) currencies in paypal's enrol plugin
which fixes the ability to use ILS (israeli SHEKEL) when used within Israeli
Moodle websites/courses context.

( currently, there is no way to use Israeli SHEKEL to enrol new users into courses!
not sure if i can call it a bug, it is just missing from the code )

so i am proposing several patches ( relevancy is according to order of comment submission )