Moved and renamed the starting and stopping scripts from the REST API
tests to a common directory. This way the MaxCtrl tests can use the same
scripts to start and stop MaxScale.
Also moved the test configuration file into the `test/` directory and
changed some of the default directory locations.
As the REST API is a part of the core, it is more appropriate for the
tests to reside there as well. Further refactoring of the testing needs to
be done to allow multiple components to use the same framework but with
different tests.
The /maxscale/ resource now supports PUT requests which modify core
parameters. As not all parameters can be changed at runtime, only
modifications to parameters that support runtime configuration are
allowed.
The tests now automatically start MaxScale before each test block and stop
it and perform cleanup after the test. This is done by simply calling the
`before.sh` and `after.sh` scripts before each test block.
