Merge pull request #187 from Ghost-script/BugFix-#184

BugFix-#184: The unread notification currently counts the user joined and left messages, we should skip them.
Moved ansible scripts for vagrant provisioning to a new dir.
Make nginx ansible scripts more customizable

with using inventory variables.
Install nodejs, npm using YUM for Redhat systems in ansible roles.
Reset waartaa vagrant playbook to older version.
Added Ansible role to build waartaa.
Fixed nodejs installation scripts for RedHat family.

Don't build and install nodejs when nodejs is already installed via YUM.
Fix some bugs in ansible scripts for setting up nginx.
Update playbook for deploying Waartaa.
Added provisioning scripts for app deployment.
Added default ansible templates for nginx deployment.

Includes templates for SSL certificate and key, and nginx conf for waartaa.
Make replica set id configurable in relica set initializing template.
Fix ansible script for pushing waartaa's build.
Added default group_vars file.