Grid(details, editable, deletable) incompatible double-usage

[laundmo]

the Grid paramters details, editable, and deletable are used for 2 distinct purposes in an incompatible manner:
- To determine whether the row has a details/edite/delete button. In this case, they can be a boolean or a callable that takes the row and returns a boolean.
- To change the details/edit/delete button URL, in this case it needs to be a str.

I cannot at the same time determine whether a row should have the details/edit/delete button and also change the URL they point at, because i cant have a callable thats also a str. I have to choose either option.

Possible solutions:
- the simplest: the callable can return the URL as well, which will be used for the button. This works because theres no need to provide a URL if the button isn't rendered for this row.
- slightly more complex: split the params into one for checking whether the buttons should be rendered, and a second for generating the button url

[Massimo DiPierro]

good catch! I like the simplest solution.