New install location + API updates

This version installs in the system folder instead of the user one, because in the latter, there is an Apple bug preventing a correct display, sorry.

Moreover, we've update some code to use new Apple APIs about when drawing text. But this is really a minor thing. The whole QLFits awesomeness is just refreshed for you to enjoy.
Assets

Better error messages

When an error prevents CFITSIO to open the FITS file, the error message of its status is brought up to the user level, for an easier debugging.

Removing slowing-down log instruction.

I deleted one damn/debug log message that was slowing-down every preview.

QLFits3 has now options!

More specifically, one can choose to:

• Always show headers, or not. By default, when an HDU has no image, its header is displayed. But some people with multiple-planes FITS files want to see only images. The header remains accessible of course, but through the usual "Toggle" button.
• Display also a short summary in thumbnails (for instance, '2 HDUs, 1 image').

3.0.4

Fixed the issue of opening files that have whitespaces and parenthesis in their path.