installation of boehm-gc include files

[Per Bothner]

I seems to me that at least gc.h from boehm-gc/include should be
installed in $prefix/include.  This is not currently installed, but it
is needed to wrap pthread calls from C code that will be linked with
Java code.  Are there any other header files that should be linked in?
gc_local_alloc.h seems plausible, for example, as does gc_alloc.h.
-- 
	--Per Bothner
per@bothner.com   http://www.bothner.com/per/