Navigator 6.7rc1 is available

[Geoff Canyon]

I found out about strokeGradient, so I updated:

1. Added strokeGradient property editing, similar to fillGradient editing.
2. Added popups for fillGradient["type"] and strokeGradient["type"], and
fillGradient["quality"] and strokeGradient["quality"].
3. Modified the property editor so start, end, via, and repeat edit inline
instead of opening the editor.
4. Fixed a bug where setting the fillGradient or strokeGradient types to
"No Gradient" failed (because that's actually an invalid value). It now
clears the gradient properly.

As usual, you can get Navigator here
<https://www.dropbox.com/s/kz3zqi4botzglgq/navigator.zip?dl=1>. Or grab it
from GitHub <https://github.com/gcanyon/navigator>.