[PATCH][IPROUTE2] Fixup u32 pretty printing

[jamal <hadi@cyberus.ca>]

Stephen,

I am going to re-send the original patch i sent (my git skills are
limited) along with two others for a total of 3. 

With these patches:

1) the default output stays as it was before and only when the user
adds a -cooked does the new pretty printing take effect. Example:

--------
hadi@lilsol:~$ tc -c filter ls dev lo parent ffff:

filter protocol ip pref 9 u32 fh 801::802 order 2050 key ht 801 bkt 0
flowid 1:16
  match IP src 10.0.0.2/32
  match IP protocol 6
  match sport 53

hadi@lilsol:~$ tc -c filter ls dev lo parent ffff:

filter protocol ip pref 9 u32 fh 801::802 order 2050 key ht 801 bkt 0
flowid 1:16
  match 0a000002/ffffffff at 12
  match 00060000/00ff0000 at 8
  match 00000035/0000ffff at 20
--------

2) A new infrastructure within u32 classifier to add more pretty
printers is added and used for raw and ipv4.

I have at least two more patches lined up, but will wait for the
application of these 3 patches or any discussion of these three first
before submitting.

cheers,
jamal