Make classpath text file if it doesn't exist

Also delimit the contents of the class path text file by newlines, not
spaces.
Merge pull request #27 from zacklb/psychjavatrouble-patch

Make classpath text file if it doesn't exist
Merge pull request #124 from kleinerm/master

Pull for PTB BETA RELEASE "Rainbows, Droids & Compute Hippies!" SP6
Merge pull request #125 from Psychtoolbox-3/master

PTB BETA RELEASE "Rainbows, Droids & Compute Hippies!" SP6

* A fix provided by zacklb for a regression introduced in new Java setup code.