Rename Registry -> Register

[ribose-jeffreylau]

According to https://guides.rubygems.org/name-your-gem/, we have the following options and implications:

• gem name: paneron-register require statement: require "paneron/register" module/class name: Paneron::Register
• gem name: paneron_register require statement: require "paneron_register" module/class name: PaneronRegister

[ribose-jeffreylau]

We'll use the one with hyphen (see https://github.com/paneron/ruby-paneron_registry/issues/3#issuecomment-2419240576)

[ronaldtse]

Thanks! Yes the namespaced option seems appropriate for this case.