JSCBC-119: Allow Function objects as map/reduce values.

Iterate through the list of views and their map/reduce
functions and convert any Function objects to their string
representations first.

Change-Id: I059056452996e6e12a4514ac04b0ba3f26d3652d
Reviewed-on: http://review.couchbase.org/38423
Reviewed-by: Mark Nunberg <mnunberg@haskalah.org>
Tested-by: Brett Lawson <brett19@gmail.com>