[Openal] Header files' location

[Garin Hiebert]

> Should the AL headers be in a directory named al? Sample code seems to 
> want them there. Matches OpenGL, so seems reasonable - but the SDK 
> installer just puts them in Include instead of Include\AL.


I'll add that to the list of things to take a look at -- it's quite 
likely handled inconsistently (which doesn't seem to be unusual in the 
Windows world, but why should we be causing more trouble, right?).

Garin