* Display aliases and custom commands in which; Fix#2810
Example output of nu after the commit is applied:
```shell
/home/leo/repos/nushell(feature/which_inspect_alias)> def docker-ps [] { docker ps --format '{{json .}}' | from json -o }
/home/leo/repos/nushell(feature/which_inspect_alias)> which docker-ps
───┬───────────┬────────────────────────┬─────────
# │ arg │ path │ builtin
───┼───────────┼────────────────────────┼─────────
0 │ docker-ps │ nushell custom command │ No
───┴───────────┴────────────────────────┴─────────
/home/leo/repos/nushell(feature/which_inspect_alias)> alias d = gid pd
/home/leo/repos/nushell(feature/which_inspect_alias)> which d
───┬─────┬───────────────┬─────────
# │ arg │ path │ builtin
───┼─────┼───────────────┼─────────
0 │ d │ nushell alias │ No
───┴─────┴───────────────┴─────────
```
* Update documentation
* Begin allowing comments and multiline scripts.
* clippy
* Finish moving to groups. Test pass
* Keep going
* WIP
* WIP
* BROKEN WIP
* WIP
* WIP
* Fix more tests
* WIP: alias starts working
* Broken WIP
* Broken WIP
* Variables begin to work
* captures start working
* A little better but needs fixed scope
* Shorthand env setting
* Update main merge
* Broken WIP
* WIP
* custom command parsing
* Custom commands start working
* Fix coloring and parsing of block
* Almost there
* Add some tests
* Add more param types
* Bump version
* Fix benchmark
* Fix stuff
* Bump Rustyline to 7.0.0
* Append history instead of always save
* Add associated type to Hinter
* Convert to using Rustyline KeyEvent
* Use AcceptOrInsertLine as struct
* Cargo fmt
* Make convert_keyevent pub
* Better naming for RL conversion
* added math round
* added math floor
* added math ceil
* added math.md examples
* moved the detection of nonnumerical values in ceil/floor/round
* math round now works on streams
* math floor now works on streams
* math ceil now works on streams
* First draft for adding a `pretty` flag to `to md`
* rustfmt
* Fix Clippy warnings
* rustfmt
* Using Clippy suggestion broken code, reverting and putting in a statement to ignore clippy warning
* Add test for `to md -p`
* WIP - compiling but not working
* semi-working
* making progress
* working except for table lines
* fmt + clippy
* cleaned up some comments
* working line colors
* fmt, clippy, updated sample config.toml
* merges
* some info on how to set colors
* WIP - compiling but not working
* semi-working
* making progress
* working except for table lines
* fmt + clippy
* cleaned up some comments
* working line colors
* fmt, clippy, updated sample config.toml
* removed extra comments
* plugin changes to support script plugins
* all platforms can have plugins with file extensions
* added .cmd, .py, .ps1 for windows
* added more trace! statements to document request and response
* WIP
* pretty much working, need to figure out sink plugins
* added a home for scripting plugin examples, ran fmt
* Had a visit with my good friend Clippy. We're on speaking terms again.
* add viable plugin extensions
* clippy
* update to load plugins without extension in *nix/mac.
* fmt
* Add deserialization of Primitive::Duration; Fixes#2373
* Implement Sleep command
* Add comment saying you should name your rest field "rest"
* Fix typo
* Add documentation for sleep command