Merged in changes from PRE101 in the prerelease branch.

Specifically, this updates libtool to version 1.5 and adds the following:
	- Added the -only-static option that we added in our previous libtool.
	- Modified the autoconf macros so that libtool uses the -G option when
	  linking on Solaris.  This allows libraries with global variables with
	  constructors to automatically run those constructors when the
	  library is dlopened().

llvm-svn: 7171