* helper/ext2cpio.c (add_link): Don't leak just-allocated buffer.
Instead, link it into links_head list.

* helper/ext2initrd.c (read_module_deps): Don't leak filename.
(ext2_make_initrd): Don't leak "outfile".
* helper/utils.c (load_file): Don't leak a file pointer.

ArchLinux used to keep its kernel in /boot/vmlinuz26 but, with
Linux 3.0, now uses /boot/vmlinuz-linux.  Instead of just changing the
kernel filename and module directory, this change removes the ArchLinux
specific code, lets febootstrap find a kernel, and then computes the
module directory from the version string extracted from the actual kernel
file.

Detect libz and, if present, define HAS_LIBZ and add -lz to Makefile's
LIBS variable.

Add entry on optional zlib package requirement.

Detect both uncompressed and gzipped kernel modules.

Some Linux distros (like ArchLinux) use gzipped kernel modules with
filenames like ext2.ko.gz.  This change modifies the filename pattern
from (e.g.) "ext2.ko" to "ext2.ko*".

When available, use libz to read the module.

The init_module system call requires uncompressed kernel module bytes.
On some systems (e.g. ArchLinux) the modules are gzipped on disk.
Libz is used to read and uncompress gzipped disk files (*.ko.gz) or
transparently read uncompressed modules (*.ko).

This saves over 5 seconds during the slow path construction of the
appliance.

The ext2fs_close2 API is present in the e2fsprogs 'next' branch and
will be in a later e2fsprogs release (thanks Ted Ts'o).

This step takes a considerable amount of time (about half of the total
construction time), so separately display a timestamped message for it.