Changed get_status to raise IdError if given a bad run uuid.
Changed API to get status of a simulation; Added commands to get JSON status.

Changed
=======

* To get nicely formatted HTML status of a simulation now is:
    run/<uuid>/status

Added
=====

* Get submission data as JSON for a single submission,
    run/<uuid>
* Get submission data as JSON for all submissions,
    run
Merge branch 'master' of https://github.com/csdms/wmt