pxpcap: Make default launcher into pxshark
pxpcap: Make default launcher into pxshark

The default if you launch pxpcap as a component now is to basically run
a little console packet dumping utility similar in spirit to tshark.

Also adds pox.lib.pxpcap:interfaces to show interface list.

diogommartins/pox,jacobq/csci5221-viro-project,kpengboy/pox-exercise,jacobq/csci5221-viro-project,VamsikrishnaNallabothu/pox,waltznetworks/pox,VamsikrishnaNallabothu/pox,kpengboy/pox-exercise,PrincetonUniversity/pox,xAKLx/pox,MurphyMc/pox,kulawczukmarcin/mypox,denovogroup/pox,xAKLx/pox,denovogroup/pox,carlye566/IoT-POX,diogommartins/pox,diogommartins/pox,waltznetworks/pox,chenyuntc/pox,carlye566/IoT-POX,xAKLx/pox,kpengboy/pox-exercise,adusia/pox,pthien92/sdn,jacobq/csci5221-viro-project,VamsikrishnaNallabothu/pox,adusia/pox,noxrepo/pox,adusia/pox,kulawczukmarcin/mypox,denovogroup/pox,carlye566/IoT-POX,xAKLx/pox,VamsikrishnaNallabothu/pox,denovogroup/pox,chenyuntc/pox,xAKLx/pox,MurphyMc/pox,MurphyMc/pox,adusia/pox,noxrepo/pox,jacobq/csci5221-viro-project,chenyuntc/pox,MurphyMc/pox,waltznetworks/pox,kulawczukmarcin/mypox,kpengboy/pox-exercise,pthien92/sdn,diogommartins/pox,noxrepo/pox,carlye566/IoT-POX,pthien92/sdn,VamsikrishnaNallabothu/pox,PrincetonUniversity/pox,PrincetonUniversity/pox,PrincetonUniversity/pox,kpengboy/pox-exercise,adusia/pox,pthien92/sdn,pthien92/sdn,noxrepo/pox,chenyuntc/pox,MurphyMc/pox,carlye566/IoT-POX,waltznetworks/pox,kulawczukmarcin/mypox,waltznetworks/pox,jacobq/csci5221-viro-project,PrincetonUniversity/pox,chenyuntc/pox,denovogroup/pox,kulawczukmarcin/mypox,diogommartins/pox