libopenflow: Refactor __ne__ methods
libopenflow: Refactor __ne__ methods

These were all identical (just negating __eq__), so they've been factored
out into the ofp_base superclass.

andiwundsam/_of_normalize,adusia/pox,diogommartins/pox,pthien92/sdn,jacobq/csci5221-viro-project,PrincetonUniversity/pox,waltznetworks/pox,jacobq/csci5221-viro-project,jacobq/csci5221-viro-project,kavitshah8/SDNDeveloper,waltznetworks/pox,MurphyMc/pox,pthien92/sdn,carlye566/IoT-POX,diogommartins/pox,kulawczukmarcin/mypox,VamsikrishnaNallabothu/pox,MurphyMc/pox,denovogroup/pox,adusia/pox,diogommartins/pox,carlye566/IoT-POX,MurphyMc/pox,carlye566/IoT-POX,diogommartins/pox,kulawczukmarcin/mypox,denovogroup/pox,PrincetonUniversity/pox,VamsikrishnaNallabothu/pox,pthien92/sdn,pthien92/sdn,jacobq/csci5221-viro-project,adusia/pox,MurphyMc/pox,kavitshah8/SDNDeveloper,PrincetonUniversity/pox,andiwundsam/_of_normalize,waltznetworks/pox,carlye566/IoT-POX,waltznetworks/pox,chenyuntc/pox,xAKLx/pox,kpengboy/pox-exercise,denovogroup/pox,kpengboy/pox-exercise,kpengboy/pox-exercise,noxrepo/pox,chenyuntc/pox,adusia/pox,kulawczukmarcin/mypox,noxrepo/pox,VamsikrishnaNallabothu/pox,kulawczukmarcin/mypox,noxrepo/pox,denovogroup/pox,VamsikrishnaNallabothu/pox,noxrepo/pox,kulawczukmarcin/mypox,PrincetonUniversity/pox,PrincetonUniversity/pox,waltznetworks/pox,chenyuntc/pox,xAKLx/pox,andiwundsam/_of_normalize,carlye566/IoT-POX,xAKLx/pox,VamsikrishnaNallabothu/pox,pthien92/sdn,chenyuntc/pox,jacobq/csci5221-viro-project,kpengboy/pox-exercise,kpengboy/pox-exercise,xAKLx/pox,adusia/pox,diogommartins/pox,denovogroup/pox,andiwundsam/_of_normalize,kavitshah8/SDNDeveloper,kavitshah8/SDNDeveloper,xAKLx/pox,MurphyMc/pox,chenyuntc/pox