Feature request: more automatic documentation for flags in --help

[olafurpg]

Just some fancy features that I think would be cool to have. It would be nice if the --help message could

• show the default values for options with default values.
• mark non-optional values as required.
• show <type> of the flag instead of "<value>". For example, <bool> for Boolean or <int*> for List[Int].

[alexarchambault]

👍 for the first two points at least.

What do you mean about the flags? That the short version should be printed before the long one?

[olafurpg]

Whoops, the angle brackets in the third bullet got rendered as html tags, see updated comment.

👍 for the first two points at least.

Awesome!