Add trickle support to urlstore

[parkan]

Version information:

0.4.16+

Type:

Enhancement

Description:

The primary use case for IA's dweb implementation on top of urlstore is serving video streams. Trickle is the preferred layout for streaming, however it's not supported by urlstore (as far as I can tell)

Looks like we can add a simple option check here to use trickle.Layout instead of balanced.Layout, though I understand that there is some desire to refactor this command before adding more complexity.

I would also accept making trickle the default here, though that's ugly.

[parkan]

@Stebalien @whyrusleeping you rock!