[Aide] missing mincludes.h

[Richard van den Berg]

Pablo Virolainen wrote:
> We should state that currently mhash 0.9.x should not be used with aide,
> because it's causes too much troubles. If one want's to use 0.9.x, use
> Christoph Ehret's patched version 1).

I don't think we should discourage the use of mhash 0.9.x altogether. 
I've added this note to the README:

   Many people have reported problems with mhash 0.9.x. If you run
   into them, please try Christoph Ehret's patches for version 0.9.4
   https://mailman.cs.tut.fi/pipermail/aide/2006-February/000419.html

Sincerely,

Richard van den Berg