Issue67 add update functionality

Fixes #67 
Fixes #69 

Adds "U" update functionality to admin interface for CRUD functionality.

- [x] Adds edit functionality to production form, toggling from add functionality
- [x]  Lists queues based on selected exchange
- [x]  List queue binding key setting to help define the production routing key value
- [x]  Makes queue list into form elements to add/remove queues from production entry in `config` field.
- [x] Queue listing is reset when exchange selection is changed
- [x] Provide reset link in queue listing to refresh list with possible queue selection based on the config file settings for the exchange.
- [x]  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
- [x]  When an existing production entry is updated the user is redirected to the production listing page.
- [x]  Adds edit link to production edit form for each entry listed on the production listing page.

In addition:
- [x] Hide `routing key` and `enable/disable` fields in add form state. Only display in edit form state.

**To test**:
- Create production entry
- Confirm that after initial production creation the form is in the edit state with a listing of queues based on the selected exchange.
  - Changing the exchange selection changes the queue listing
  - Unselecting a queue removes the queue from the production
  - The list of queues can be refreshed / reset by selecting the "Reset Queue" link
- All other production settings can be updated
- Edit a production entry by selecting the name of the entry which is an edit link