I would like to suggest that a MIME type be added for gnuplot source files. 
There is no IANA standard for this MIME type, and while there are several
unofficial "x-" types in the wild (text/x-gnuplot, image/x-gnuplot,
application/x-gnuplot), I believe that application/x-gnuplot is probably the
most appropriate.  There is also no universally agreed-upon filename extension,
though *.gp, *.gplt, and *.gnuplot seem to be the most common.  Ergo:

  <mime-type type="application/x-gnuplot">
	<comment>Gnuplot plot files</comment>
	<glob pattern="*.gp"/>
	<glob pattern="*.gplt"/>
	<glob pattern="*.gnuplot"/>
  </mime-type>