Datastreaming: Add system tests for ICP/filewriter integration

[DominicOram]

As a developer I would like to be sure that the ICP continues to integrate with the filewriter to write valid nexus files that contain event data.

Acceptance Criteria

• There is a system test that starts/stops a run through the ICP and confirms that the filewriter creates a valid NeXus file with event information.

[DominicOram]

Pointing to reflect how long I actually spent on this.

[DominicOram]

Changing points to reflect only review required

[DominicOram]

For testing building the ICP locally is a pain. However the build server will push the result of the ICP PR to CompGroup\ICP\ISISICP\DAE3\DEV\configure_broker\1\service\x64. You should then be able to replace your local ICP (at ICP_Binaries\isisdae\x64) with this one to test.

[FreddieAkeroyd]

Replacing just the isisicp binaries may caused an issue if the isisicp.default.properties is then out of date. I've added a new file to make this easier, if you open the latest numbered subdirectory in CompGroup\ICP\ISISICP\DAE2\DEV\configure_broker you should find an update_dev.bat which if you run will update the ICP_Binaries\isisdae files on your local computer

[ThomasLohnert]

Some questions on https://github.com/ISISComputingGroup/system_tests/pull/45

Please also add information about adding your user to the docker-users group at https://github.com/ISISComputingGroup/ibex_developers_manual/wiki/Datastreaming#system-tests

[DominicOram]

Thanks @ThomasLohnert. Docs have been added in system test README and in https://github.com/ISISComputingGroup/ibex_developers_manual/wiki/Datastreaming#system-tests.

[DominicOram]

Given all associated PRs are merged and system tests are passing I'm going to call this done, thanks @ThomasLohnert and @FreddieAkeroyd