Shift version description to top of section

The other commands have the following layout:

  ### {command name}

  {one-line description}

  * *Options:* ...
  ...
  * *Exit code:* ...

  {additional notes}

  {example}

so its good to follow that pattern for 'version'.

This commit also removes a dangling "The version" which snuck in with
ffa124c (Add a 'version' command, 2015-09-14).

Author: wking

runtime.md

@@ -16,6 +16,8 @@ Global options may take positional arguments (e.g. `--log-level debug`), but the
 
 ### version
 
+Print the runtime version and exit.
+
 * *Options* None are required, but the runtime may support options.
 * *Standard streams*
   * *stdin:* The runtime may not attempt to read from its stdin.
@@ -25,9 +27,6 @@ Global options may take positional arguments (e.g. `--log-level debug`), but the
   * *stderr:* The runtime may print diagnostic messages to stderr, and the format for those lines is not specified in this document.
 * *Exit code:* The runtime must exit with zero.
 
-Print the runtime version and exit.
-The version
-
 Example:
 ```sh
 $ funC version