An enforcer for some opinionated rules about coupling in C++

This is an exercise that is helping to refactor a large, old C++ codebase (along with https://github.com/prozacchiwawa/braceIt).

Because this codebase exhibits high coupling (specifically, a god object, an all-static class, and a few other highly coupled classes all of which contain methods or parts of methods that belong to each-other), I am writing this to output a sort of refactoring roadmap and as a kind of scorecard. I have already reduced one 15kloc source file from 50 violations of these current rules to 1, resulting in an object that can finally exist in a unit test.

The last rule, banning coupling to specific namespaces is intended as a way of holding coupling back once some level of decoupling has been achieved. How well this works in practice is a social, rather than a technological problem. It can't be worse that what's been tried before however.

Currently enforces the following rules:

• Expressions that generate non-const references to global storage are not allowed.
• Bare new and delete operators are not allowed.
• Namespaces may be specified where non-abstract classes are not allowed.
• Basic detection of expressions generating references to structs and classes in banned namespaces, except from functions or methods defined in those namespaces.