change default store, global bug fixes

Defaults to storing in memory instead of redis to make deployment
easier, Fixed an in issue with global when no posts are in the store
yet, also made sure maxid doesn't go under post id 1
caching bug fix, error'd callback return arrays where needed

dataPost not being scoped local was causing corruption when trying to
cache posts. postToAPI/getHastag/getChannelMessage are expected to
return arrays even on error now.
streaming empty user record guard

on user events, apparently app.net has sent an empty user object, so
now we guard against that. Also some minor whitespace clean up.
Merge branch 'master' of https://github.com/neuroscr/AppDotNetAPI