Apply suggestions from code review

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Co-authored-by: Michael Davis <mcarsondavis@gmail.com>

book/src/keymap.md

@@ -238,7 +238,7 @@ TODO: Mappings for selecting syntax nodes (a superset of `[`).
 #### Window mode
 
 Window mode is accessed by typing `Ctrl-w` in [normal mode](#normal-mode),
-this layer is similar to Vim keybindings as Kakoune does not support window.
+this layer is similar to Vim keybindings as Kakoune does not support windows.
 
 | Key                    | Description                                          | Command           |
 | -----                  | -------------                                        | -------           |

book/src/remapping.md

@@ -4,7 +4,7 @@ Helix currently supports one-way key remapping through a simple TOML configurati
 file. (More powerful solutions such as rebinding via commands will be
 available in the future).
 
-To remap keys, create a `config.toml` file in your `Helix` configuration
+To remap keys, create a `config.toml` file in your `helix` configuration
 directory (default `~/.config/helix` on Linux systems) with a structure like
 this:
 
@@ -75,6 +75,6 @@ Ctrl, Shift and Alt modifiers are encoded respectively with the prefixes
 
 Keys can be disabled by binding them to the `no_op` command.
 
-You can find a list of available commands at [Keymap](https://docs.helix-editor.com/keymap.html).
+You can find a list of available commands in the [Keymap](https://docs.helix-editor.com/keymap.html) documentation.
 
 > Commands can also be found in the source code at [`helix-term/src/commands.rs`](https://github.com/helix-editor/helix/blob/master/helix-term/src/commands.rs) at the invocation of `static_commands!` macro and the `TypableCommandList`.

book/src/themes.md

@@ -131,7 +131,7 @@ supported by your terminal emulator.
 
 ### Inheritance
 
-Extends other themes by setting the `inherits` property to an existing theme.
+Extend other themes by setting the `inherits` property to an existing theme.
 
 ```toml
 inherits = "boo_berry"

book/src/usage.md

@@ -121,7 +121,10 @@ If you have a selection that wraps `arg1` (see the tree above), and you use
 Alt-n, it will select the next sibling in the syntax tree: `arg2`.
 
 ```js
-func([arg1], arg2, arg3) > func(arg1, [arg2], arg3);
+// before
+func([arg1], arg2, arg3)
+// after
+func(arg1, [arg2], arg3);
 ```
 
 Similarly, Alt-o will expand the selection to the parent node, in this case, the