* Split help message into brief and full help
Demonstrate on ansi command
Brief help is printed when running `help commands` so it doesn't clutter
the table. Full help is printed when normal help message is requested
(e.g., `help ansi`, `ansi --help`, etc.).
* Split long command descriptions
Some are not split, just edited to be shorter.
* Capitalize the usage of all commands
* Make sure every usage ends with dot
* Fix random typo
* move commands, futures.rs, script.rs, utils
* move over maybe_print_errors
* add nu_command crate references to nu_cli
* in commands.rs open up to pub mod from pub(crate)
* nu-cli, nu-command, and nu tests are now passing
* cargo fmt
* clean up nu-cli/src/prelude.rs
* code cleanup
* for some reason lex.rs was not formatted, may be causing my error
* remove mod completion from lib.rs which was not being used along with quickcheck macros
* add in allow unused imports
* comment out one failing external test; comment out one failing internal test
* revert commenting out failing tests; something else might be going on; someone with a windows machine should check and see what is going on with these failing windows tests
* Update Cargo.toml
Extend the optional features to nu-command
Co-authored-by: Jonathan Turner <jonathandturner@users.noreply.github.com>
