Proposed release of 2.1.6

[Alan DeKok]

A.L.M.Buxey at lboro.ac.uk wrote:
> no showstopper just yet... however, noted error in Makefile
> (spotted when doing the install)
> 
> sed: can't read pool.h: No such file or directory
> sed: can't read smodule.h: No such file or directory
> 
> 
> indeed, Makefile mentions pool.h and smodule.h but they dont seem
> to exist anymore

  They're in the "master" branch, not in "stable".  I'll go fix that,
thanks.

  Alan DeKok.