Changed syn.query to return a generator.  This handles large query results by automatically chunking the query into smaller pieces and returning them as the user iterates over the generator.
Merge branch 'master' of https://github.com/Sage-Bionetworks/synapsePythonClient into QueryChunking

Conflicts:
	synapseclient/client.py
Moved the new chunked query functionality into a separate method (syn.chunkedQuery).  Restored old method (and updated its comment).

Command-line query method uses chunked query.
Added a commented-out unit test for the chunked query method.  The unit test may or may not be viable due to the massive query required to test this method.
Following Bennett and Chris's advice, the unit test lowers the number of rows per query and tests a query of 15 Entities chunked into 5 calls.
Merge pull request #60 from kaysoky/QueryChunking

Added alternate query method (chunkedQuery) to return a generator