[tests] Don't import QUnitTestCase into tests' global namespace Unittest's test loader will try to execute QUnitTestCase's test_javascripts method. However this class is intended to be subclassed, not to be executed directly. This change has the following consequences: * slightly faster test execution * almost all rtags warnings are gone

Latest changes 
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* table of `all latest changes`_

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.. _all latest changes: ../view?rql=Any+M%2CX+WHERE+X+modification_date+M+ORDERBY+M+DESC+LIMIT+30