tagmethod

name	tagmethod
description	Convert a standard class method to a form with a constrained 'this' type, for use with a tagged assumption for

Assumption Tags are a type in the form {name?: true|false} Tags refers to the valid set of assumption tags. DefaultTags refers to the default set of tags. MethodToChange is the method in the class to change. Arguments are the method's arguments NewTags refer to the set of new tags the user wants. Tags are strings that map to booleans.

Convert ```ts class Class<OPT extends {Tags} = DefaultTags> { MethodToChange(Arguments) { } }

To 

```typescript
class Class<OPT extends {Tags} = DefaultTags> {
    MethodToChange(this: Class<OPT & {NewTags}>, Arguments) {
    }
}