add new field in wb_callback_s struct, change some names in json generator
change default buffer size
Add authentication routine

Not used yet.
Fix compile errors
Auth integrated with existing `transport`
Update test mock
Merge pull request #1 from rampage644/master

Authentication
Fix get_json_key function
Fix get_json_key function2
fixed some memory problems
Merge pull request #2 from pkit/auth

fixed some memory problems
Fix compile errors
Fix building token header entry
Auth if sending for the firsst time
Fix dangerous buffer write
Merge pull request #3 from rampage644/master

Fixes, auth on first time
Removed unnecessary map entries
Retrieve tenant id from auth as well
Merge pull request #4 from rampage644/auth

Auth
Add read callback

Read callback is used to flush with strict interval.
Fix not allocating yajl handle after flush.