Support reverse proxies that terminate HTTPS

[dhardiker]

Bamboo has a fair number of absolute URLs in it, not least redirects during setup. If you have a reverse proxy (such as Amazon's ELB) in front of a Bamboo server docker instance (such as on Amazon's ECS) without this patch, Bamboo will redirect you from HTTPS to HTTP constantly making the application unusable.

This patch allows you to specify the BAMBOO_SCHEME env var to either http or https (defaulting to https). We use xmlstarlet to set the appropriate connector attributes in the Tomcat server.xml file.