Don't use C++ comments in generated code

Change-Id: Iaadbd22f11970a0f566f42ab436ede74ccbcf83b
Reviewed-on: http://review.couchbase.org/29968
Reviewed-by: Trond Norbye <trond.norbye@gmail.com>
Tested-by: Trond Norbye <trond.norbye@gmail.com>