Auto-generate markdown command docs (#4451)

* Finish updating

* a couple improvements

* Update renames

* cleanup examples

docs/commands/skip_while.md

@@ -0,0 +1,23 @@
+---
+title: skip while
+layout: command
+version: 0.59.0
+---
+
+Skip elements of the input while a predicate is true.
+
+## Signature
+
+```> skip while (predicate)```
+
+## Parameters
+
+ -  `predicate`: the predicate that skipped element must match
+
+## Examples
+
+Skip while the element is negative
+```shell
+> echo [-2 0 2 -1] | skip while $it < 0
+```
+