Squish Tests: Experiment setup period types

As a developer I would like to verify the following behaviour using Squish:

- In the `DAE` perspective, in the `Experiment Setup` tab, change the period type.
- Verify that the settings for each type are as expected.
- Software: PC controlled - single setting `Number of software periods`.
- Hardware: DAE internal control - `Hardware periods sequences`, `Output delay`, `Source`.
- Hardware: External signal control - Same as DEA but with `Hardware periods sequences` and frames disabled.
- For `Select Period Source`:
- Verify that `Specify Parameters` shows a table of parameters.
- Verify that `Read from file` shows a file selection drop down menu.