plscheme - plscheme: Fix a small --safe-r5rs argument parse error and

Log Message:
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Fix a small --safe-r5rs argument parse error and add fancy naming support aware
of untrusted/trusted PL.

Modified Files:
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plscheme:
install.sh (r1.6 -> r1.7)
(http://cvs.pgfoundry.org/cgi-bin/cvsweb.cgi/plscheme/plscheme/install.sh.diff?r1=1.6&r2=1.7)