|__ plans >>> [c] contains test plans, can be git checkouts, symlinks to local dirs, or the source itself
| |__ suite-a >>> test plans can be grouped in suites (which in turn can be nested); this enables you to host many test plans in a single repo / directory.
| | |__ plan-1 >>> source of a test plan identified by suite-a/plan-1 (relative to $TESTGROUND_HOME/plans)
| |__ plan-3 >>> source of a test plan identified by plan-3 (relative to $TESTGROUND_HOME/plans)
|__ sdks >>> [c] hosts the test development SDKs that the client knows about, so they can be used with the --link-sdk option.
|__ data >>> [d] data directory
[c] = used client-side // [d] = used mostly daemon-side.