gnu-smalltalk: generational GC requires libsigsegv

In 64 bit, --without-libsigsegv implies --disable-generational-gc

The build was failing for me, now at least it builds by disabling
libsigsegv it seems to work (on small programs)

Closes #17576.

Signed-off-by: Jack Nagel <jacknagel@gmail.com>
leveldb: also build the leveldbutil

The tool is really useful to dump the contents of leveldb
databases

Closes #17581.

Signed-off-by: Jack Nagel <jacknagel@gmail.com>
Xcode.version: return dunno as a string and not a symbol
XQuartz.version: return dunno as a string and not a symbol
ghc: still fails with clang 425

Closes 17575.
sleuthkit 4.0.2

The Sleuth Kit 4.0.2 now includes fiwalk, so this commit
also removes the fiwalk formula.

Closes #17584.

Signed-off-by: Adam Vandenberg <flangy@gmail.com>
curl-ca-bundle: use prebuilt bundle

The mk-ca-bundle script uses perl modules that don't work consistently
across proxies, etc. so just package it up.

Fixes #17286.
nettle 2.6

Closes #17587.

Signed-off-by: Adam Vandenberg <flangy@gmail.com>
gnutls 3.1.7

Closes #17586.

Signed-off-by: Adam Vandenberg <flangy@gmail.com>
nsd 3.2.15

Closes #17593.

Signed-off-by: Adam Vandenberg <flangy@gmail.com>
pakchois 0.4

Closes #16767.

Signed-off-by: Adam Vandenberg <flangy@gmail.com>