Registered model redefinition

[dgasull]

Design and implement a way to "redefine" or "replace" an already registered class. This will replace the current classes deployed in execution environments and objects belonging to the class will be lost/removed to avoid serialization issues. The call should warn the user about it. A name for the API call can be overwriteModel or replaceModel ...

[dgasull]

This also refers to bsc-dom/javaclay#9

[alexbarcelo]

Maybe it would make more sense (for the user) to have an explicit deleteModel and not an overwrite/replace.

A deleteModel should (seems obvious!) remote all the objects belonging to the class. And once the model has been deleted, the new one can be registered again.

Disclaimer: This may be finnicky in scenarios in which a registered class has attributes with the type of the class being deleted, e.g. class A contains an attribute of B and class B is being deleted. Though this consideration should also be extrapolated to objects referencing objects.