Merge branch '1.6.x' into 'master'

beat/backend/python/algorithm.py

beat/backend/python/baseformat.py

beat/backend/python/data.py

beat/backend/python/exceptions.py

beat/backend/python/execution/__init__.py

beat/backend/python/execution/algorithm.py

beat/backend/python/execution/database.py

beat/backend/python/execution/helpers.py

beat/backend/python/execution/loop.py

beat/backend/python/execution/messagehandlers.py

beat/backend/python/helpers.py

beat/backend/python/scripts/databases_provider.py

beat/backend/python/scripts/execute.py

beat/backend/python/scripts/loop_execute.py

...t/prefix/algorithms/autonomous/invalid_loop_output/1.json

...est/prefix/algorithms/autonomous/invalid_loop_output/1.py

...kend/python/test/prefix/algorithms/autonomous/loop/1.json

...ackend/python/test/prefix/algorithms/autonomous/loop/1.py

...python/test/prefix/algorithms/autonomous/loop_user/1.json

...d/python/test/prefix/algorithms/autonomous/loop_user/1.py