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resolves#4869
# Description
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Adds a `help escape` command that can be used to display a table of
string escape sequences and their outputs.
```nu
help escapes
```
```nu
help escapes -h
```
The command should also appear in the list displayed when tab
autocompleting on `help`.
# User-Facing Changes
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helps us keep track of breaking changes. -->
Users can now use a new `help escapes` command to output a table of
string escape sequences and their outputs.
# Tests + Formatting
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# After Submitting
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Need to update docs to reflect existence of the new `help escapes`
command.
# Description
Make sure that our different crates that contain commands can be
compiled in parallel.
This can under certain circumstances accelerate the compilation with
sufficient multithreading available.
## Details
- Move `help` commands from `nu-cmd-lang` back to `nu-command`
- This also makes sense as the commands are implemented in an
ANSI-terminal specific way
- Make `nu-cmd-lang` only a dev dependency for `nu-command`
- Change context creation helpers for `nu-cmd-extra` and
`nu-cmd-dataframe` to have a consistent api used in
`src/main.rs`:`get_engine_state()`
- `nu-command` now indepedent from `nu-cmd-extra` and `nu-cmd-dataframe`
that are now dependencies of `nu` directly. (change to internal
features)
- Fix tests that previously used `nu-command::create_default_context()`
with replacement functions
## From scratch compilation times:
just debug (dev) build and default features
```
cargo clean --profile dev && cargo build --timings
```
### before

### after

# User-Facing Changes
None direct, only change to compilation on multithreaded jobs expected.
# Tests + Formatting
Tests that previously chose to use `nu-command` for their scope will
still use `nu-cmd-lang` + `nu-command` (command list in the granularity
at the time)