CAEN: Simulator and Tests

As a supporter of IBEX I want to be able to test the CAEN alongside everything else as part of the IOC/System Tests

**Acceptance Criteria**
1. There is a test to ensure that the CAEN IOC starts and functions suitable when items such as EPICS Base are updated.
1. There is a test to ensure that grouping still functions.

**Notes**
1. There is a HVCAENSIM_01 IOC, however, this did not display the error behaviour, as such a Lewis emulator would be beneficial for testing
1, The change from Base 3.14 to 3.15 introduced a startup error, as such suitable tests should be included to avoid this occurring again