Enable creating apps using config files without explicitly writing an app.py file to simplify setup.

[MagnusEngh]

Description

In order to simplify setup and make it easier to share apps, would be neat if it was possible to create a fully functional editingframework app using mostly configuration files like the below example:

variable_selector:
    år:
        type: year
    orgnr:
        type: primary-ident
    nace: 
        type: classification
        klass_code: 123

modules:
    EditingTable:
        inputs: ["år"]
        states: []
        get_data_func: src.functions.my_table_func
    skjemadataeditor:
        settings: ....