added first version of jhbuild support for buzztrax

@ensonic can you please take a look and possible merge/comment?

Currently I do not know why we need the (not working) XDG_DATA_DIRS ... but also buzztrax does not compile clean.

But this can be used as a good starting point.

I have used gstreamer as additional module and used version 1.1.90. Please be aware of this.

Thanks,

- waffel