Added script to send random cosm style data, and an svg file for testing
Added simple pipeline display
Removed old field from pipeline.

Removed junk printing into svg files
Added view of pipelines with most recent image.
Added description field to pipelines
Fixed pipeline init so it always has a valid image
Updating example to use parameters and do pretty things
Changed the way GeneratorState handles parameters. Now uses a JsonField
to make life much much easier.

Now gets and sets parameters correctly
Removed GeneratorStateParameter completely
Worked the parameter changes all the way through.
Changed the way that Generators manage adding/updating parameters to fix
some bugs
Refactored how files are stored. Now there is a StoredOutput for any
combination of (Pipeline, run_id, file extension, total or partial
output).

Pipelines store their current state in (e.g.)
/data/working/pipeline_1_complete.png (where 1 is id of the pipeline)

They also update the StoredOutput, which can then be looked up by
Generator id or Endpoint id etc.
Using stored stuff in view to show the recent images that a Pipeline has
made