More little grass bugs

[Angus Carr]

In my continuing quest to get this image classified...

I have recently discovered a bug affecting i.in.erdas.
It seems that the byte-swapping is not being performed properly on my computer
(Intel).

I added a switch to force swapping on the header to make it work, then I
realized afterwards that the -DATT_386 flag was not being set.

It is a good idea to have a switch anyway, because ERDAS files can be in either
order. Another way to deal with it is to check whether the number of bands is
reasonable (ie. somewhere near 1-20, rather than somewhere in the 1536 range
like this file I have here) and then prompting the user about it in wierd
situations. 

Any thoughts?
If nobody has any comments, I will put in my patched i.in.erdas with the
appropriate flag added.

Angus Carr.