Merge branch 'develop' into master_merge_develop_v3

 Major refactoring for robustness and including Let's Encrypt support

  Fixes #62 #63

Update download path and sha256 sum to reference latest

Fixes #60

tasks/main.yml: Improve configuration of /etc/hosts (#53)

- Adds localhost back
  - Improves regexp to escape periods properly
  - Inserts to the beginning of file if not present

Closes #35, thanks @jautz!

Workaround: Fix mongodb user on centos with /sbin/nologin - new bug i…

…n 2.4.0

Needs executable on users with /sbin/nologin or /sbin/false because
it uses $SHELL:

ansible/ansible#26741 (comment)

Upgrade nodejs dependency to 4.5.0 LTS to meet RC min requirements

  - Added 'rocket_chat_node_version' default w/ ver. 4.5.0
  - Change node-version-specific vars to be generic
    - i.e. rocket_chat_node_10_40_path -> rocket_chat_node_path
  - Updated README to reflect changes
  - Fixes #33

Fix bug where correct file is downloaded and upgrade is never notified (

#32)

- Addendum to 5e86223
- Resolves #25

Remove forever daemon in lieu of plain Upstart on Ubuntu 14 (#30)

The previous method of using the forever monitor daemon with upstart
failed at being able to write to the pid-file upon reboot. This showed
up in Vagrant testing and I believe it has something to do with the fact
that we're creating the pidfile manually within the play.

I have prior experience with NodeJS+Upstart and it turns out that
forever isn't actually necessary at all. With `console log` and
`respawn` directives, and an unforked process, Upstart properly tracks
the PID (without a pidfile), respawns the process should it die, and
logs by default to `/var/log/upstart/rocketchat.log`

This changeset removes the following tasks and has the added benefit of
simplifying the play overall:

- Ensure Forever (NodeJS) is installed [Ubuntu 14]
- Check to see if the Rocket.Chat log file is present [Ubuntu 14]
- Ensure the Rocket.Chat log file is present [Ubuntu 14]
- Ensure the Rocket.Chat pid file is present [Ubuntu 14]

The former log-file path has been replaced with a symlink pointing to
the new logfile path.

This fixes #11

Update README.md to include info about branch changes (#28)

Merge branch 'travis_ci' into ansible_2.1

This merge brings in much needed automated testing from travis ci,
testing the playbook on several docker containers. Currently testing
on our supported distros:

1. Ubuntu 16.04 and 14.04
2. Debian 8
3. Centos 7

Ansible 2.1 Support