Limit buffer tracing to 50 in order to limit large output, unless
the user over rides the max "sh trace max <number>".
Add trace filtering, to be able to only trace packets that were
processed by a specific node or exclude packets processed by a node.
Example, only include packets processed by error-drop:
# trace filter include error-drop 1
# trace add dpdk-input 1000000
<wait for packets, to come in>
# show trace
Change-Id: I5d9e15d2268ea55e6ef87b2b8756049c49b2791b
Signed-off-by: Todd Foggoa <tfoggoa@cisco.com>
0bcc9d511e