Expose JIT Module's "register_attribute" to Python (#35630)
Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/35630
Prefix underscored for now because the semantics of this method can be
confusing. It adds a new attribute to the *type*, which can be shared
by several objects.
Test Plan:
Next diff in stack uses it, and has unit tests.
Imported from OSS
Differential Revision: D20904253
fbshipit-source-id: dcbf60eacf0e0e075c19238165aa33954aa73b5f
