update dist.sh docker build
update dist.sh docker build

no longer uses local cross-built binaries
(now built in separate docker container)

"-f" flag for "docker tag" is obsolete

also misc checklist/instructions updates

mreiferson/nsq,nsqio/nsq,nsqio/nsq,ploxiln/nsq,ploxiln/nsq,bitly/nsq,jehiah/nsq,mreiferson/nsq,jehiah/nsq,rpau/nsq,mreiferson/nsq,mreiferson/nsq,jehiah/nsq,nsqio/nsq,nsqio/nsq,bitly/nsq,nsqio/nsq,rpau/nsq,sparklxb/nsq,ploxiln/nsq,ploxiln/nsq,sparklxb/nsq,bitly/nsq,mreiferson/nsq,rpau/nsq,sparklxb/nsq,sparklxb/nsq,rpau/nsq,jehiah/nsq,ploxiln/nsq,bitly/nsq,rpau/nsq,sparklxb/nsq,jehiah/nsq,bitly/nsq