1678: Refactor clap_generate r=CreepySkeleton a=pksunkara
I have copied the code from [clap_generate]( https://github.com/clap-rs/clap_generate) and refactored the structure a bit.
This new structure will allow people to write their own generators using our `Generator` trait which will contain some helpers (Still working on polishing them).
Co-authored-by: Ole Martin Ruud <barskern@outlook.com>
Co-authored-by: Pavan Kumar Sunkara <pavan.sss1991@gmail.com>
1664: Import structopt r=pksunkara a=CreepySkeleton
OK, here is about 50% of what's left to import.
`impl StructOpt for Box<impl StructOpt>` is not imported because layouts of `StructOpt` and `Clap` are too different. I'll work it out after the import is done.
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Co-authored-by: CreepySkeleton <creepy-skeleton@yandex.ru>
Co-authored-by: Cecile Tonglet <cecile.tonglet@cecton.com>
Co-authored-by: David McNeil <mcneil.david2@gmail.com>
