Revise hashbang snippet added in d181298
Revise hashbang snippet added in d181298

* Prefix changed to "apl". Typing this is somewhat easier than "#".
* Hashbang path changed to use /usr/bin/env, which is more portable.
* Tab-stops removed; users won't likely need to change the hashbang path
  or arguments. Having tab-stops also makes it impossible to indent code
  after insertion, as the cursor jumps back to the hashbang directive.
* An ")OFF" command has been included, necessary to terminate GNU APL.

Alhadis/language-apl