Unit test workin in Py2 and Py3

[vokimon]

The following changes are done:

• Add github actions workflows for CI that install dependencies in Py2 and Py3 and pass the unittests. Functional tests (using erppeek) and Destral tests are not run yet.
• Add a gha workflow to publish the non-erp module as we push the version tag.
• Dependencies somutils and plantmonitor have been put under similar workflows (CI and pypi publish).
• somutils and plantmonitor are already published. generationkwh is not, it should be published after this branch is merged.
• To get dependencies (somutils and plantmonitor) in green, conditional dependencies for Py2.7 had to be set as several libraries stopped suporting Py2. Althought it works standalone, interactions with dependencies of a full erp installation is to be checked. Conditional restrictions are documented in setup.py of each project.
• Commonalities (isodate, run_destructive_test and so on...) were moved to somutils.
• Removed wavefile dependency (from b2btest, now modularized)
• success and coverage badges are included both in the README and in qa-control, besides the circle-ci badges

[vokimon]

TODO: El coverage se entrelaza con el de Cercle-ci