Support partial restrictions about airline HOT 6 CLOSED

Turns out we can't use Annotation as the general type of a restriction but we can use Class<? extends Annotation> so the definition will need to look something like the following:

@Option(name = "--example", arity = 2)
@PartialRestriction(index = 0, restriction = NotBlank.class)
@NotBlank
private List<String> examples;

And we'll need special logic in MetadataLoader to load the list of @PartialRestriction and modify generated restrictions as necessary

I have run into one bug which is that if you want to partially apply a postValidate() based restriction this does not work because postValidate() assumes the ability to see the full state. So we need to change that to finalValidate() method and introduce a new postValidate() method that sees the strongly typed value at the point at which it is introduced

from airline.

More thoughts:

• Will need an @Partials to cope with the case where you want to define multiple @Partial on a single field
• Need to work out how to implement HelpHint for PartialRestriction in a sane manner
• MetadataLoader needs to obtain and act upon the @Partial/@Partials that are present

from airline.

Will also need to document Migration because some of these changes are breaking

Finally it would be ideal if restrictions that make no sense as @Partial error ASAP

from airline.

Also it would be nice if the current means of enforcing restrictions is moved from the parsers into ParseState so people can't write parsers that don't enforce the restrictions and we don't have to duplicate code so much

from airline.

Everything but HelpHint support is done

from airline.

Added HelpHint support so closing this now

from airline.