[PATCH 00/14] Add a type-safe API to registries

[Tom Tromey]

This series adds an optional type-safe API to the gdb registry
feature, and converts various modules to use it.

I don't think this is the final form for registries -- in the long run
I suppose I'd like to turn them into a CRTP mixin class.  However,
this series seems like a reasonable step along the way, providing type
safety and using policy classes for destruction.

Let me know what you think.

Regression tested by the buildbot.

Tom