sw/qa/README: document that complex/unoapi are Java tests

Change-Id: Ibaeefe795c8318824fe3d158871eae0477ef0fc4

sw/qa/README

-You can find different types of Writer tests here, the most interesting ones:
+You can find different types of Writer tests here, the following directories
+are available:
 
-- core/filters-test: loads different file types (see SwFiltersTest::testCVEs()
-  for the list of supported filter types), and only makes sure Writer does not
-  crash. To add new tests, you just need to drop in the test files to the
-  relevant directory, no code change is necessary.
-- core/uwriter: this test has access to private Writer symbols, add new tests
-  here if you need that.
-- extras: see its own README -- executes import and export filters and asserts
-  the UNO model to verify the resulting document is the expected one.
+- core:
+  - filters-test: loads different file types (see SwFiltersTest::testCVEs() for
+    the list of supported filter types), and only makes sure Writer does not
+    crash. To add new tests, you just need to drop in the test files to the
+    relevant directory, no code change is necessary.
+  - uwriter: this test has access to private Writer symbols, add new tests here
+    if you need that.
+- extras:
+  - see its own README -- executes import and export filters and asserts the
+    UNO model to verify the resulting document is the expected one.
+  - also, any new C++ test that links to libsw (but does not need access to
+    private Writer symbols) should go in this directory, whether using the UNO
+    API or the internal one.
+- complex: JUnit-based tests using the UNO API
+- unoapi: JUnit-based test trying to get/set every UNO property, etc.