losetup: return EXIT_FAILURE on unsuccessful -f

Reported-by: Ruediger Meier <sweet_f_a@gmx.de>
Signed-off-by: Karel Zak <kzak@redhat.com>
lib/colors: add support for @term and /home/kzak

Signed-off-by: Karel Zak <kzak@redhat.com>
lib/colors: allow to temporary disable colors

Signed-off-by: Karel Zak <kzak@redhat.com>
lib/colors: support schemes customization

 * parse terminal-colors.d/*.scheme files, expected format is

    <name> <color-sequence>

 * supported color sequences:

     - color name (e.g. "red")
     - dir_colors compatible xx;yy (e.g. 01;31) where the sequence may
       contains control chars like \e \a  ..etc.

 * scheme is parsed on demand

Signed-off-by: Karel Zak <kzak@redhat.com>
libsmartcols: use new colors API

Signed-off-by: Karel Zak <kzak@redhat.com>
hexdump: use new colors API

Signed-off-by: Karel Zak <kzak@redhat.com>
lib/colors: update man page

Signed-off-by: Karel Zak <kzak@redhat.com>
dmesg: support colors customization

Signed-off-by: Karel Zak <kzak@redhat.com>
hexdump: add --color to the man page

Signed-off-by: Karel Zak <kzak@redhat.com>
fdisk: support colors customization

Signed-off-by: Karel Zak <kzak@redhat.com>
cfdisk: update man page COLORS section

Signed-off-by: Karel Zak <kzak@redhat.com>
agetty: fix odd check for chardev/tty

References: https://bugzilla.redhat.com/show_bug.cgi?id=1069902
Signed-off-by: Karel Zak <kzak@redhat.com>
lib/colors: add to the man page hint about $HOME stuff

Signed-off-by: Karel Zak <kzak@redhat.com>