e2image.c, mke2fs.c, mklost+found.c, tune2fs.c, util.c, uuidgen.c: Fix
gcc -Wall complaints, including one bug in tune2fs caused by a block
automatic shadowing version of the variable we really wanted to use,
which broke the logic testing to see if the filesystem was mounted.
ChangeLog, MCONFIG.in:
(gcc-wall-new): Added new target which forgoes the make clean so we
only check the newly modified .c files.
badblocks.c, dumpe2fs.c, e2label.c, mke2fs.c, tune2fs.c, uuidgen.c:
For platforms that don't define optarg.h, manually define optarg and
optind.
ChangeLog, main.c:
main.c: For platforms that don't define optarg.h, manually define
optarg and optind.
ChangeLog, unix.c:
unix.c: For platforms that don't define optarg.h, manually define
optarg and optind.
uuidgen.c, uuidgen.1.in: Created command-line utility to generate
UUIDs.
fsck.c (fsck_device, execute): Don't dereference a null pointer when
checking a filesystem not in /etc/fstab.