Autogenerate missing docs (#3514)

* Autogenerate missing docs

* Update ansi.md

* Rename question mark command docs

* Delete empty?.md

docs/commands/with-env.md

@@ -0,0 +1,36 @@
+# with-env
+Runs a block with an environment variable set.
+
+## Usage
+```shell
+> with-env <variable> <block> {flags} 
+ ```
+
+## Parameters
+* `<variable>` the environment variable to temporarily set
+* `<block>` the block to run once the variable is set
+
+## Flags
+* -h, --help: Display this help message
+
+## Examples
+  Set the MYENV environment variable
+```shell
+> with-env [MYENV "my env value"] { echo $nu.env.MYENV }
+ ```
+
+  Set by primitive value list
+```shell
+> with-env [X Y W Z] { echo $nu.env.X $nu.env.W }
+ ```
+
+  Set by single row table
+```shell
+> with-env [[X W]; [Y Z]] { echo $nu.env.X $nu.env.W }
+ ```
+
+  Set by row(e.g. `open x.json` or `from json`)
+```shell
+> echo '{"X":"Y","W":"Z"}'|from json|with-env $it { echo $nu.env.X $nu.env.W }
+ ```
+