Added a cleaner way to install demo source so that installed versions use a
simplified makedefs/makerules.
Small fix to get osgText to compile with Solaris CC. Constructor declared
with a non-const argument, but implemented with const argument.
the Make directory is left with four files only :
makedefs
makerules
makedirrules
instrules
These work for all platforms supported so far, which include :
Linux
Irix
Solaris
MacOSX
Cygwin
FreeBSD