Improve robustness of the test suite

Tests now inherit a global set of rules.
Enforce a timeout per test.
Allow three attempts per test.
Introduce a logging mechanism for test name and duration.
Add a wait for the js and ajax elements to silence.

Also removed some unnecessary concordion tests, fixed the autocomplete
search function and removed NoScreenshot annotations where not
required.
Merge pull request #419 from zanata/test-suite-robustness

Improve robustness of the test suite