Fix test suite
The test suite is still too fuzzy, and the py35-qt5 target had to be quarantined.
This PR does a large refactoring of the tests (mostly the taurus/qt
ones) to improve the situation. With it, the testsuite seems finally stable for all the targets. As a summary, here is what changed:
- refactor all the qt tests to use pytest-qt (this seemed to fix many of the "random" crashes during test execution). And deprecate old unittest-based qt test utilities and TimeOut DS.
- force to use PyTango >=9.3.1 for all targets (I had to provide my own conda package of PyTango v9.3.1 which was not officially available, see ab6888bb )
- Add some pytest-based utilities for new tests
- Fix a few bugs in the code that affect the tests (8efbe875 , 14d94b8d, e48a2d91, dcb68317, )
- Remove taurus usages of deprecated APIs of dependencies (1d44c7a2, 46ddb2cf, b5173ad8, 964b18fa, 6cb42ffd, 4aaf110a, 5bc24ad6) and configure the tests to treat future occurrences as errors (66e4d32e)
- change the tango docker images to use a mirror from those of ska-docker to avoid availability issues of ska's registry
Also, this PR removes the allowed-to-fail tests (python2 ones and flake8) from travis matrix (to avoid wasting time). They can be run locally and/or re-enabled at any moment