Adding style

[Geegee]

Adding a light theme to Qudi both for Qt and the RichJupyterConsole.

Description

Added Style sheets and Images from the same source as the already used dark theme. Increased customization of Qudi console through config option and settings (maybe it is better to just have it in settings and use StatusVar?)

Motivation and Context

If you ever escape your dark lab.

How Has This Been Tested?

Just on dummy opening various GUIs. In Pulsed there was one issue were I couldn't see the check boxes in the predefined methods methods selector (was still usable though).

Tested on linux.

Screenshots (only if appropriate, delete if not):

Types of changes

• [ ] Bug fix (non-breaking change which fixes an issue)
• [ x] New feature (non-breaking change which adds functionality)
• [ ] Breaking change (fix or feature that would cause existing functionality to not work as expected)

Checklist:

• [ ] My code follows the code style of this project.
• [ ] I have documented my changes in the changelog (documentation/changelog.md)
• [ ] My change requires a change to the documentation.
• [ ] I have updated the documentation accordingly.
• [ ] I have added/updated for the module the config example in the docstring of the class accordingly.
• [ ] I have checked that the change does not contain obvious errors (syntax, indentation, mutable default values).
• [ ] I have tested my changes using 'Load all modules' on the default dummy configuration with my changes included.
• [ ] All changed Jupyter notebooks have been stripped of their output cells.

[Neverhorst]

Please open this PR in the new qudi-core repo.