Initialize and Storage

Added initialize and shutdown methods for measurement
Added environment variable expand method for sqlite storage
Added first implementaition of file only storage
Added storage test to test execution
Added `#!/usr/bin/env python3` to test_runner
Improvement of measure save in seperate process with signal handling
Improvement of configuration and its test
Moved the `sqlite_factory` to a class, so its possible to initiate the
  storage in the save process and not before