Configure.pl --parrot_is_shared option doesn't work.

[Andy Dougherty]

Configure.pl currently offers a --parrot_is_shared option, apparently with 
the intent of controlling whether libparrot.so (or equivalent) or 
libparrot.a is built and used.  Unfortunately, it doesn't work.  

If building libparrot.so is the default on a particular platform (e.g. 
linux), setting --parrot_is_shared=0 doesn't stop libparrot.so from being 
built and used.

On the other hand, if building libparrot.a is the default on a particular 
platform (e.g. solaris), setting --parrot_is_shared=1 doesn't cause 
libparrot.so to be built and used.

I suspect there are two issues.  First, hints files shouldn't usually 
unconditionally override command-line settings.  That's what the linux 
hints file is doing now, I think.  Second, there are apparently a bunch of 
other related under-documented variables that need to be set in response 
to parrot_is_shared, but are currently set unconditionally.

-- 
    Andy Dougherty		doughera at lafayette.edu