Aliases should ensure they don't duplicate a canonical name or other alias

[eeverman]

The current rules for org.yarnandtail.andhow.api.Name aliases prevent names from starting or ending with a '.', however, they could otherwise contain a dot and thus look like a canonical name.

It seems like 'out' names should have almost no rules - perhaps the need is to create a particular report.
Runtime alias 'in' collisions should be detected and runtime exception stopped.

Options:

• The rules for 'in' names might just ban dots completely. This might be a problem for some cross compatibility w/ legacy systems, but it would ensure aliases don't accidentally collide.
• In the interest of allowing legacy compatability w/ config that might already contain dots, allow it, detect collisions at runtime, and add some docs advising against new apps using dots.

Certainly an alias should not duplicate a canonical name and this should be detected as early as possible.