examples/ip_pipeline: add more functions to routing pipeline

examples/ip_pipeline: add more functions to routing pipeline

This patch adds following features to the
routing-pipeline to enable it for various NFV
use-cases;

1.Fast-path ARP table enable/disable
2.Double-tagged VLAN (Q-in-Q) packet enacapsulation
for the next-hop
3.MPLS encapsulation for the next-hop
4.Add colour (Traffic-class for QoS) to the MPLS tag
5.Classification action to select the input queue
of the hierarchical schedular (QoS)

The above proposed features can be enabled
(or disabled) through the parameters specified
in configuration file as below;

[PIPELINE0]
type = ROUTING
core = 1
pktq_in = RXQ0.0 RXQ1.0 RXQ2.0 RXQ3.0
pktq_out = TXQ0.0 TXQ1.0 TXQ2.0 TXQ3.0
n_routes = 4096
n_arp_entries = 1024
ip_hdr_offset = 142
arp_key_offset = 64
l2 = qinq
qinq_sched = no

The LPM table entries might include additional
fields depending upon the packet encapsulation
(Q-in-Q, MPLS)for the next-hop. The CLI
commands for adding or deleting such entries
to LPM table have been implemented. Action
handlers for QinQ and MPLS encapsulation,
classification action to select the input queue
of the hierarchical schedular(QoS) and adding
colour (Traffic-class for QoS) to the MPLS
tag have been implemented.

Signed-off-by: Jasvinder Singh <jasvinder.singh@intel.com>
Acked-by: Cristian Dumitrescu <cristian.dumitrescu@intel.com>