Autogenerate missing docs (#3514)

* Autogenerate missing docs

* Update ansi.md

* Rename question mark command docs

* Delete empty?.md

docs/commands/exec.md

@@ -0,0 +1,26 @@
+# exec
+Execute command.
+
+## Usage
+```shell
+> exec <command> ...args {flags} 
+ ```
+
+## Parameters
+* `<command>` the command to execute
+* ...args: any additional arguments for command
+
+## Flags
+* -h, --help: Display this help message
+
+## Examples
+  Execute 'ps aux'
+```shell
+> exec ps aux
+ ```
+
+  Execute 'nautilus'
+```shell
+> exec nautilus
+ ```
+