[request] Class VDict needs basic iterator funtionality

[RaiMan]

not really a bug --- should be evaluated with renewal of api

noted here, because my question expired: https://answers.launchpad.net/sikuli/+question/99867

In the doc it reads: The syntax of the visual dictionary data type is modeled after that of the built-in Python dictionary data type.

it should be possible to say, what currently is not:
for (k,v) in vd.items(): # were vd is a VDict()

and some of the other basics:
http://docs.python.org/library/stdtypes.html#mapping-types-dict