Remove loguru dependency in favor of standard logging

[mwartell]

Armory-library needs to drop loguru in favor of standard logging. This requires

• Refactoring logs.py to use logging
• Removing imports of loguru in source files
• Removing the loguru package dependency

[mwartell]

Blocked because it needs further thinking on what is needed and where it is in app / core-library division of labor.

[mwartell]

We will defer this until we get any indication that armory-library users are hampered by the non-standard logging.

[mwartell]

In discussion with Ari, we ratified that as a library, Armory needs to do this. So we shall.