Test: Install integration versions in a tmpdir and add logging

Make the "npm run test-versions" script (integration/adapters-run.js)
more robust by installing packages in a temporary directory
entirely separate from the repository's working directory.

Also capture the output of the test runs in a file so that one
can easily inspect and find out why a version is failing. This
can then be used to report issues upstream (if it's a new version),
or to fix something on our end of it is genuine, or to document
it in failing-versions.js if it is a known issue with a past release.

- qunitjs:
  Make the list of old versions that are failing complete
  and document why they fail.

- jasmine:
  Version 2.5.2 and later failed due to a default reporter killing
  killing the process (again). This needs to be fixed on our side
  by clearing the default reporters. Fixed as part of this commit
  since it didn't need a change to the adapter.

  Version 3.0 and later failed due to randomized order.
  Disable in our test.

- mocha:
  Version 8.0 and later are currently failing due to skipped
  tests not being recognised correctly. I've filed
  #116 to follow
  up on this in a later commit as it looks like that would require
  a source change to the adapter.

.gitignore

@@ -1,2 +1,3 @@
 /node_modules
+/log
 /*.log

README.md

@@ -78,6 +78,16 @@ runner.on('runEnd', function (globalSuite) {
 JsReporters.TapReporter.init(runner);
 ```
 
+### Adapter support
+
+| Testing framework | Supported | Latest version tested | Unresolved issues
+|--|--|--
+| QUnit | QUnit 1.20+ | ✅ `qunit@2.11.1` (September 2020) | None
+| Jasmine  | Jasmine 2.1+ | ✅ `jasmine@3.6.1` (July 2020) | None
+| Mocha | Mocha 1.18+ | ✅ `mocha@7.2.0` (May 2020) | 
+
+See also [known issues](test/versions/failing-versions.js).
+
 ### API
 
 **autoRegister()**