0.pre8.109

0.pre8.109
	#+sb-threads check for Linux 2.4, because it won't work in 2.2
	In the process, rename early_kernel to linux_sparc_siginfo_bug,
	just to make its purpose a little more obvious

	Export WITH-TIMEOUT and TIMEOUT from SB-EXT.  TIMEOUT is now a
	SERIOUS-CONDITION not an ERROR