IOC: Hide development/advanced IOCs

When accessing the IOC list, there are currently a number that are meant for development or advanced use that are not especially useful for the large majority of users. Specifically the IOCs suggested are:

- TEST
- MOTORSIM
- SIMPLE
- CONTROLSVCS

It would be useful if IOCs could be identified as being not for display. This could be done either:

- As a list in the database server (as done with IOCS_NOT_TO_STOP
- As an addition to the config.xml

The former would not require a change to the DB and would be easier but it means decentralising more of the IOC configuration. Arguably though, whether an IOC is advanced or not is a decision for the database server and not for individual IOC so I'm slightly favouring the former.

As a user, I would like to not be shown IOCs that are not useful for instrument operation, but I would like to be able to display them if explicitly requested. Please discuss with the group which IOCs should be entered into this category. The list above was a draft from Matt on Slack so is not definitive.

Acceptance criteria:
- [ ] There exists a toggle button in the IOC control dialog for displaying advanced IOCs
- [ ] The toggle is off by default
- [ ] Advanced IOCs are shown if and only if the toggle is active

- [ ] There exists a toggle button in the configuration editor for displaying advanced IOCs
- [ ] The toggle is off by default
- [ ] Advanced IOCs are shown if and only if the toggle is active