Merge branch 'branch-4.2' into master-branch-4.2-merge

See merge request cds/advligorts!350

Adding Noise module parameter that will allow the designer to specify a  seed in order to re-run with the same RNG, also initializing the RNG with a tsc based seed by default. Updating some language around seeding the noise part.

See merge request cds/advligorts!349

convert the sequencer to C++

See merge request cds/advligorts!343

 * Updated code to use size/type specific ints as intermediate types instead of casting to int.
 * Updated simple_pv_types.hh to allow the ait_data_type template to export the relevant ait... type that corresponds with the value.

Merge branch4.2 into master

See merge request cds/advligorts!348

seed in order to re-run with the same RNG, also initializing the RNG
with a tsc based seen by default. Updating some language around seeding the noise part.

 * Removed copies of checkFileCrc from the epics sequencer, standalone_edc, and sdf_monitor.c
 * Updated the logic in checkFileCrc to return -1 when the file name is NULL or the file cannot be opened
   * as per documentation.

 * Removed a call 'bear', which was used to understand the build of the sequencer.
 * checkFileCrc needs C linkage for of the backend sequencer bits.
   * It should be moved into a header file

 * Adding a type to represent the EPICS types of channels we deal with so it can be abstracted from the iocsh and CAS/CA versions of the types.
 * the channel access varient of the sequencer builds again.

 * Reworking the simpleIntPv and simpleIntAttribute interface to be templates to allow for semi-arbitrary int PV types.
   * Done to support int, uint, ushort types in the epics sequencer.

 * test_casdf_seq -> casdf_seq
 * test_seq -> model_seq

* Added test builds of the sequencer to the cmake to facilitate building and debugging (non-functional as it does not build the dbd file, cmd file, ...
* Wrap the local EPICS variables in a new type to promote type safe read/write of data, plus give us a point to allow mocking the interface out.
* the casdf sequencer does not build right now.

The sequencer now builds for both regular models and slow controls sdf.

Added a simple_range abstraction (a container for a begin/end iterator pair) as a view over the fixed_size_vectors.

Also added some more checks for fixed_size_string to ensure it can meet the requirements to be in the vector.