Add generic hook-scripts to TW to automatically update/delete/add remote tasks

[bratne]

Add a generic way to update remotes when working in taskwarrior/bugwarrior. Re-using authentication methods etc.

Suggested pilot: Use #1011 and #1012 as baseline implementation.

NOTE: This increases the usability of bugwarrior, but might be to taskwarrior-specific. However reusing the auth-mechanisms makes it sensible to make this part of bugwarrior.

[ryneeverett]

See #135. I'm more open to this than Ralph was at that time, but we couldn't agree to merge such a feature without at least a detailed design proposal, if not an implementation.

It sounds like you do have a concrete idea how you'd like to implement this in a hook though. If all we have to do is add a post_import hook and expose the configuration to it, that seems reasonable. However, implementing the script you'd run with the hook -- especially in a "generic way" -- sounds like a lot of work.