[syslinux] SYSLINUX 2.20-pre4 available

[H. Peter Anvin]

Yep, -pre4.  I've had a massive cleanup urge and have been doing things 
like actually move common variables into the .inc files where they 
belong.  This also means NASM 0.98.38 is absolutely required, since it 
uses those new features extensively.

This release also contains code to compress label statements in memory, 
although it's not actually turned on yet.  Once turned on it should mean 
a much more reasonable label limit of about 700 in a typical 
configuration (obviously the exact number depends on the complexity of 
the arguments.)

	-hpa