LB-1900 Concurrent request support via child_process exec

Concurrent request support via child_process exec
Separate server functionality in server.js
and application functionality in app.js

Issues with logger.
LB-1900 Concurrent request support via child_process exec

Fixed http error codes.
Fixed logger issue.
LB-1901 Better logging

Support error logging even if no options.error given.
Log even if the obj are not as expected.
Merge pull request #221 from nistormihai/child-process-exec

Child process exec