tests independent from local mss_settings.json

[Reimar Bauer]

while running tests some of the tests are influenced by a local mss_settings.json

We should base tests on the builtin defaults or use a test config from a test directory.

[Reimar Bauer]

tests become independent from local mss_settings.json, fixes #191

→ <<cset bea4100ed8ff>>

[Reimar Bauer]

Merged in ReimarBauer/mss/testenv (pull request #355)

tests become independent from local mss_settings.json, fixes #191

→ <<cset a1e28fc16e67>>