Fix/improve the SSL configuration

- Do not extend config.express.serverOptions with config.ssl before
  the config validation is done: the former is undefined by default
  (#843) and that's OK as it would fire a validation warning otherwise.

- Use _.merge instead of the undefined _.recursive.defaults to set the
  default values of config.express.serverOptions (#844). Use _.extend
  if the serverOptions wasn't defined by the user's config.
Drop extraneous greater-than.
Merge pull request #852 from hellojwilde/patch-1

Drop extraneous greater-than.
Added CONTRIBUTE.md to help improve contributions
>>
>> The CONTRIBUTE.md message will now always show up whenever opening a PR or
>> issue.
>>
>> Closes #717
Merge pull request #869 from yoshuawuyts/master

Added CONTRIBUTE.md to help improve contributions
Merge pull request #845 from wolneykien/master

Fix/improve the SSL configuration
Merge pull request #851 from sazze/master

added suport for winston adapters
Update README.md

Bumped latest stable release version in readme.
Fixed issue where specifying a socket to omit in Model.publish calls would cause the Model classroom to be used, instead of the specified room.
Merge pull request #903 from saghaulor/patch-1

Update README.md
Use `io` from the local namespace
Merge pull request #933 from drosen0/patch-2

Use `io` from the local namespace