Auto-generate markdown command docs (#4451)

* Finish updating

* a couple improvements

* Update renames

* cleanup examples

docs/commands/each.md

@@ -1,40 +1,24 @@
-# each
-Run a block on each row of the table.
+---
+title: each
+layout: command
+version: 0.59.0
+---
 
-## Usage
-```shell
-> each <block> <subcommand> {flags} 
- ```
+Run a block on each element of input
 
-## Subcommands
-* each group - Runs a block on groups of `group_size` rows of a table at a time.
-* each window - Runs a block on sliding windows of `window_size` rows of a table at a time.
+## Signature
+
+```> each (block) --numbered```
 
 ## Parameters
-* `<block>` the block to run on each row
 
-## Flags
-* -h, --help: Display this help message
-* -n, --numbered: returned a numbered item ($it.index and $it.item)
+ -  `block`: the block to run
+ -  `--numbered`: iterate with an index
 
 ## Examples
-  Echo the sum of each row
-```shell
-> echo [[1 2] [3 4]] | each { echo $it | math sum }
- ```
 
-  Echo the square of each integer
+Multiplies elements in list
 ```shell
-> echo [1 2 3] | each { echo ($it * $it) }
- ```
-
-  Number each item and echo a message
-```shell
-> echo ['bob' 'fred'] | each --numbered { echo $"($it.index) is ($it.item)" }
- ```
-
-  Name the block variable that each uses
-```shell
-> [1, 2, 3] | each {|x| $x + 100}
- ```
+> [1 2 3] | each { 2 * $it }
+```