Consider passing current Play application via parameters instead of relying on importing play.api.Play.current

[Alex Wei]

A concern was raised during review of https://bitbucket.org/atlassianlabs/atlassian-connect-play-scala/pull-request/8/solves-issue-36-by-converting-achostws-to/diff that a class/object that import play.api.Play.current may be loaded before the application is started.

This is of low priority right now as we have not received any reports that this may be an issue. If anyone is affected by this, please add a comment here.