[PATCH 073/153] kill sd_packer_client, create TwitterPacker in twitter.aurora.common_internal
[PATCH 073/153] kill sd_packer_client, create TwitterPacker in twitter.aurora.common_internal

Step N in the Aurora OSS epic.
 Summary:
  - kill sd_packer_client, rip twitter-specific authentication methods from twitter.packer.packer_client
  - create TwitterPacker wrapper with authentication, takes in a twitter.aurora.common.cluster object
  - create TwitterPacker.from_cluster_name which references a cluster from TWITTER_CLUSTERS (twitter.aurora.common_internal.clusters)

RB_ID=178789

(sapling split of a38d5483d6f704c8e69f700c020c045483908299)

pombredanne/commons,pombredanne/commons,Yasumoto/commons,cevaris/commons,VaybhavSharma/commons,pombredanne/commons,jsirois/commons,nkhuyu/commons,atollena/commons,brutkin/commons,abel-von/commons,abel-von/commons,ericzundel/commons,pombredanne/commons,WCCCEDU/twitter-commons,ericzundel/commons,atollena/commons,jsirois/commons,brutkin/commons,brutkin/commons,VaybhavSharma/commons,jsirois/commons,brutkin/commons,abel-von/commons,cevaris/commons,jsirois/commons,VaybhavSharma/commons,brutkin/commons,cevaris/commons,abel-von/commons,VaybhavSharma/commons,WCCCEDU/twitter-commons,nkhuyu/commons,abel-von/commons,nkhuyu/commons,atollena/commons,Yasumoto/commons,ericzundel/commons,VaybhavSharma/commons,WCCCEDU/twitter-commons,Yasumoto/commons,atollena/commons,ericzundel/commons,jsirois/commons,Yasumoto/commons,WCCCEDU/twitter-commons,atollena/commons,ericzundel/commons,cevaris/commons,nkhuyu/commons,WCCCEDU/twitter-commons,nkhuyu/commons,pombredanne/commons,Yasumoto/commons,cevaris/commons