Most of the abstract base test classes we have were previously @Ignored.
However, there were also some other tests ignored. Having two ways to
quiet tests is confusing, and clearly it has caused some tests
to get lost in the fold.
This change moves all base test classes to use the "TestCase" suffix,
which is not picked up by the test class name pattern. It also removes
@Ignore from (almost) all tests, and adds it to forbidden apis.
And since we were renaming, I shorted base test class names to use
"ES" instead of "Elasticsearch". I type this a lot of types a day,
and I have heard others express a similar desire for a shorter name.
closes#10659
1e12d03252