Feature request: Allocating dynamic port range for task

I was asked to open new ticket after this conversation https://groups.google.com/forum/#!topic/nomad-tool/LUqywl3fV3U
Short recap:
I need to run some multimedia service using nomad that dynamically opens ports to serve clients. It has two settings to limit its port usage basePort and portSpan, effectively this two settings form a range [base, base + span].
It turns out that nomad can't allocate contiguous port range for a task. I think port range settings is not uncommon, especially for multi media streaming servers.

Here for for example, Wowza Streamer, that uses a configurable UDP port range to stream media over RTP (http://www.pagefabric.com/blogs/2013/05/18/how-to-enable-firewall-friendly-streaming-in-wowza-media-server/)
I think it will be nice for nomad to support this feature.

The issue names no files, tests, or entry points. Start by locating Nomad's task port-allocation implementation and existing port configuration documentation; done should mean a task can request and receive a contiguous dynamic range suitable for services such as Wowza Streamer.

Written by the indexing model from the issue text.