Output test results in XML reports instead of to standard output

This is a workaround for a problem with the integrated TeamCity JUnit
listener which is not thread safe. Without this the test results are
completely mixed up in TeamCity. For more information, see
http://youtrack.jetbrains.com/issue/TW-33176.

All standard JUnit test reports is put in result/reports. For uitest
there are three report directories: result/reports-tb2,
result/reports-tb3 and result/reports-integration to be able to clean
the directories before running a given type of tests.

This change is based on the separate fixes by John.

Change-Id: I2f0dee416f6745544636f2f3dcea0d0832ff8076