Remove settings as a hard dependency for Dependency.py

[LexiconCode]

Description

This request removes settings as a hard dependency for Dependency.py

Related Issue

#676

Motivation and Context

This make sure that Caster checks dependencies before third party packages are called. This allows Dependency.py to check for missing or version specific dependencies.

How Has This Been Tested

This has been tested

• Online and off-line Caster mode
• Removal of toml dependency
• Past existing unit tests
• Created a test package` parsing of readme
• Mouse grids have been tested

Types of changes

• Docs change / refactoring / dependency upgrade

Checklist

• I have read the CONTRIBUTING document.
• My code follows the code style of this project.
• My code implements all the features I wish to merge in this pull request.
• All new and existing tests pass.

Maintainer/Reviewer Checklist

• Basic functionality has been tested and works as claimed.
• New documentation is clear and complete.
• Code is clear and readable.

[LexiconCode]

With the removal of Dependency.py from the Nexus. The following needs to be handled so it's not dependent on the nexus.

def mouse_alternates(mode, nexus, monitor=1):
    if nexus.dep.PIL:

Code