plscheme - htdocs: Update ./install.sh and compilation examples with

Log Message:
-----------
Update ./install.sh and compilation examples with respect to new
trusted/untrusted PL availability.

Also remove globally shared variables section.

Modified Files:
--------------
htdocs:
index.html (r1.28 -> r1.29)
(http://cvs.pgfoundry.org/cgi-bin/cvsweb.cgi/plscheme/htdocs/index.html.diff?r1=1.28&r2=1.29)