Removed redundant task.incoming() code.

This change has null effect, it just removes some pre multi-threading cruft and renames some associated function calls.  With multi-threading ```task.incoming(message)``` became merely a wrapper for pushing messages onto a queue, but we ended up with a slightly confusing mix of calls to the wrapper and direct message queue puts. There's really no need for the wrapper - it was just the quickest way of converting the existing code to use a queue - so I've removed it.

@matthewrmshin - please review.