Issue67 add update functionality

** Not complete, for review / discussion only **

- Adds edit functionality to production form, toggling from add functionality
- Lists queues based on selected exchange
- List queue binding key setting to help define the production routing key value
- Makes queue list into form elements to add/remove queues from production entry in `config` field.
- When a new production entry is created the user is redirected to the edit version of the form allowing for further queue and routing key settings
- When an existing production entry is updated the user is redirected to the production listing page.
- Adds edit link to production edit form for each entry listed on the production listing page.