Be consistent in fluent interface
Operands and Options populate a list of detected arguments instead of holding a value.

This avoids side effects and make it safe to parse multiple inputs from the same command line definition
Make it easier to work with arguments input when parsing
We no longer need separate builders now that Option and Operand do not hold any value
Provide usage guidance when using fluent interface
An attempt to implement type safety
Make Args typesafe as well