* extends BaseModalFormView to hold general logic for processing GET and POST requests for BaseModalForm endpoints
* refactors uuid check to use a specific parameter instead of kwargs
* fixes css bug where modal form input elements would not be visible
* refactors check view for intervention from function to class
* refactors DeductionViews to inherit from extended BaseModalFormView
* refactors deduction views on interventions and eco accounts from function to class based
* introduces basic checks on shared access and permission on BaseView on dispatching --> checks shall be overwritten on inheriting classes
* splits compensation/views/eco_account.py (+700 lines) into separate files in new module
* view files can now be found in /compensation/views/eco_account/...
