(ConsoleLoadingBar) Added an Update(string message) override

And a minor refactoring

Conflicts:
	src/ConsoleLoadingBar/SingleLoadingBar.cs

Conflicts:
	src/ConsoleLoadingBar/SingleLoadingBar.cs
(ConsoleLoadingBar) Added Behavior.AppendEtaToMessage and the code to support it

I was considering simply adding Humanizer as a dependency, but it might
bloat the project.

Conflicts:
	src/ConsoleLoadingBar/SingleLoadingBar.cs

Conflicts:
	src/ConsoleLoadingBar/SingleLoadingBar.cs
(Solution) Created v0.3