Subject: remove OSTNG references. Make client change for
request prefetch. add safe dictionary checking for arbitrary
data.

removed the OSTNG reference common/models.
Added a method to check the dictionary of arbitrary data
sent in from the command line that won't blow up on a keyError.
requests made a change from prefetch to stream and inverted
the logic.

Change-Id: I8741640912485cf3c631eee20a0bddb8c2f9a714
Merge "Subject: remove OSTNG references. Make client change for request prefetch. add safe dictionary checking for arbitrary data."