Fix macOS camera / microphone / photo library permissions

[gtm19]

Problem

Built macOS app crashed when camera access was requested, due to the fact that (whilst the Entitlements.plist was being updated properly) the expected info was not being added to Info.plist

This PR fixes this issue by ensuring that, when the user provides permissions.camera, permissions.microphone, or permissions.photo_library, the messages are added to Info.plist under the relevant property key.

Changes

• Added tests to test_create.py for macOS
• Patched macOSCreateMixin in __init__.py for macOS
• Updated documentation accordingly

PR Checklist:

• [x] All new features have been tested
• [x] All new features have been documented
• [x] I have read the CONTRIBUTING.md file
• [x] I will abide by the code of conduct