[Hat] Hat-Gui, new tool

[Olaf Chitil]

Neil Mitchell wrote:

> I have now committed hat-gui, with support for only hat-stack.
>
> This version requires a split version of HatStack, where the existing
> HatStack.hs is divided into HatStack.hs for the libary and
> HatStackText.hs for the console input/output. Since this breaks the
> makefile's for Linux, and is a reasonable amount of restructuring, I
> thought I'd send the new versions of HatStack and HatStackText for
> comments first. They are attached. Is this split/names/interface
> acceptable?

Great. I wonder whether it would be more sensible if the HatStack itself 
wouldn't do the trace file opening, hence also not get a FilePath as 
argument. In your GUI you want to combine several tools. So you open the 
trace once and then call the models of several tools. You might want to 
put the little code for rectifying the filename and opening the file 
into a general hat tool library. I guess the existing tools have a bit 
of code duplication.

Btw, feel free to add comments in the code ;-) I fear the code isn't 
well documented.

Ciao,
Olaf