Starting in Spina 2, BaseModel, BaseView, and BaseCollection's

configurable attributes are now defined as static, allowing them to be

accessed outside of instances. This is important for subclasses.
These make use of the new prototypeAttrs option, which ensures they'll

be accessible on the prototype, allowing Backbone to behave as normal

and for instances to continue accessing using this.
Types for both the static and instance/prototype versions are set on

these base classes. Since static is incompatible with generics, we use

the most base type for these there, but the ones on the prototype are

typed as expected. Subclasses may still define types for their versions.
Some attributes (events, modelEvents, and defaults) are also set

up to auto-merge between parents/subclasses. This means that subclasses

no longer have to manually call _.defaults or _.extends, passing in

the parent class's attribute (but at the same time, it won't hurt if

they still do). This will keep things more maintainable going forward.

Porting existing code in Review Board to set the appropriate attributes

as static, and verified that instances and subclasses could properly

access and extend these.