@petebacondarwin deserves credit for most of this commit.
This allows you to specify a regex and serializer function instead
of the path DSL in your route declaration.
```
@RouteConfig([
  { regex: '[a-z]+.[0-9]+',
    serializer: (params) => `{params.a}.params.b}`,
    component: MyComponent }
])
class Component {}
```
Closes #7325
Closes #7126