Support IoC container(s) for initializing verb instances.

[nemec]

Instead of requiring a default constructor, add the ability to initialize verbs from IoC containers and other factories.

[nemec]

This is now supported via an IVerbFactory parameter to the parser.

var opt = new OptionsWithGitVerbs();
var factory = new SimpleVerbfactory
{
    { () => new GitAdd() },
    { typeof(GitCommit), () => new GitCommit("My default message") }
};

var parser = new CliParser<OptionsWithGitVerbs>(
    opt, ParserOptions.None, new AutomaticHelpGenerator<OptionsWithGitVerbs>(), factory);

parser.Parse("add myfile.txt otherfile.txt".Split());