Add missing double quotes to readlink call. Opening paths with spaces now works.

I was trying to make it possible to double click on .pde files on Ubuntu 13.04 following http://forum.processing.org/topic/ubuntu-12-10-launch-pde-files-from-nautilus
I noticed that files found in paths that include spaces would not open. I fixed it by adding double quotes to a readlink call at the end of the Processing launcher script. Other similar calls to readlink in the same file already included double quotes.
revised color conversion methods
removed the glFinish hack to handle #1714, as it seems that JOGL 2.0.2
solved the issue.
Merge pull request #2027 from hamoid/master

Add missing double quotes to readlink call. Opening paths with spaces no...
set viewport in PGL.drawTexture(), fixes #1869
added implementations of textAscent(), textDescent(), and
textWidthImpl() so the text rendering in P2D/P3D matches JAVA2D output
divide width and height by 2f to properly take into account resolutions
that are not divisible by 2
increasing ROUND_JOIN_THRESHOLD in LineStroker to allow for line
segments with points closer to each other (see #1927)
added MAX_POINT_ACCURACY constant to cap number of segments used when
drawing an ellipse
fixes #2003
fix options parsing to handle spaces in the names