py/objclosure: Implement closure attributes.
py/objclosure: Implement closure attributes.

Just proxy all attribute operatons to the underlying function object.

Change-Id: I4f90c75db510352d6306e2e7ca8b0b81b10aa45b
Signed-off-by: Paul Sokolovsky <9dc5061f178bb11813e14f1ed02ba27eaf21fa5d@users.sourceforge.net>

pfalcon/micropython,pfalcon/micropython,pfalcon/micropython,pfalcon/micropython,pfalcon/micropython