Add tests for autoload

[artoonie]

Uses the new test harness in #990 to add a regression test for #987.

While the tests fail without #987 merged into this PR, they would pass once #987 is merged in. Not merging them for now to reduce dependencies between PRs until we decide merge order.

This PR:

1. Creates Common.java for shared test helpers
2. Creates GuiFunctionalityTests.java for non-tabulation tests, currently only testing autoload but I expect we can use it to test other functionality that only affects the GUI
3. In GuiConfigController.java, splits out the autoload code into a separate function that can be tested. (For a cleaner diff, make sure you "Hide Whitespace" in github. It's mostly moving code to another function without real changes.)
4. Updates TabulatorTests to use the new functionality in Common.java
5. Modifies the CVRs to remove aliases. They're tested elsewhere and they complicate autoload. \CDF and Dominion have "IDs" which autoload will find, creating differences between those formats and ES&S where IDs aren't used. Simpler to simply remove the concept of IDs for these specific tests.

The base branch was changed.

[yezr]

lgtm