No longer support LZMA-compressed initrds
Also support XZ-compressed initrds ;-)

I *do* have an excuse: resqut is taking shape, and takes up a
prohibitive amount of space when not using XZ compression.
Allow randomised kernel loading (ALSR)
Remove EVM (prevented booting) & unneeded AppArmor
Remove sys-apps/gradm

Only useful on grsecurity-patched kernels, which I no longer use.