checkpatch.pl: add ability to ignore various messages

Some users would like the ability to not emit some of the messages that
checkpatch produces.  This can make it easier to use checkpatch in other
projects and integrate into scm hook scripts.

Add command line option to "--ignore" various message types.  Add option
--show-types to emit the "type" of each message.  Categorize all ERROR,
WARN and CHK messages with types.

Add optional .checkpatch.conf file to store default options.
3 paths are searched for .checkpatch.conf
    .             customized per-tree configurations
    $HOME         user global configuration when per-tree configs don't exist
    ./scripts     lk defaults to override script
The .conf file can contain any valid command-line argument and
the contents are prepended to any additional command line arguments.
Multiple lines may be used, blank lines are ignored, # is a comment.

Update "false positive" output for readability.

Update version to 0.32
Signed-off-by: Joe Perches <joe@perches.com>
Acked-by: Mike Frysinger <vapier@gentoo.org>
Cc: Andy Whitcroft <apw@canonical.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>