Note if each library is Octave-compatible

[apjanke]

Test out each library in the list with Octave to see if it works there, and add an indicator to each library item to indicate yes/no.

[apjanke]

TODO: make little icons for Octave compatibility. One that's just a small Octave logo, and one that's the Octave logo with that slashed-circle "No" sign over it. And maybe one with the little "! in a yellow triangle" caution sign to indicate partial compatibility.

[apjanke]

I added badge icons. You can use them by putting ![Octave Compatible][octave] or ![Not Octave Compatible][no-octave] in the list's Markdown source.