Remove last bit of platform-specific code from core

[YabMas]

Most of the core functionality is made platform-agnostic, this aided reuse and shows good code-practices. There's some platform-specific code left, but it's not considered worth it to remove it now because making the core platform-agnostic is not a goal for the project so it's been decided to put effort in the real goals. This issue documents the last platform-specific core-name-spaces in the core.

• authentication
• some domain-schema's