Resolve "Time to refactor utils?"

Closes #509 (closed)

bilby/core/utils/__init__.py

+from .calculus import *
+from .cmd import *
+from .colors import *
+from .constants import *
+from .conversion import *
+from .counter import *
+from .docs import *
+from .introspection import *
+from .io import *
+from .logger import *
+from .plotting import *
+from .progress import *
+from .samples import *
+from .series import *
+
+#  Instantiate the default argument parser at runtime
+command_line_args, command_line_parser = set_up_command_line_arguments()
+#  Instantiate the default logging
+setup_logger(print_version=False, log_level=command_line_args.log_level)