Icon Picker - support for hideColor and size

[leekelleher]

Description

umbraco/Umbraco-CMS#13079 added a feature to hide the colour selection from icon picker overlay panel. This PR adds support for this feature, on Umbraco v11.2+.

This PR also adds an option for the Icon Picker's editor size (e.g. large or small).

Types of changes

• Documentation change
• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)

Checklist

• My code follows the coding style of this project.
• My changes generate no new warnings.
• My change requires a change to the documentation.
• I have updated the corresponding documentation.
• I have read the CONTRIBUTING and CODE_OF_CONDUCT documents.