Added HTTPS_METHOD=nohttps to disable SSL site

[kamermans]

This feature complements HTTPS_METHOD=nohttp, which disables the HTTP site. For containers with HTTPS_METHOD=nohttps set, the template sets is_https to false, which treats everything as if there was no matching certificate.

This solves issue #573, in which a user needs to disable the HTTPS site for a specific container with a subdomain that happens to match the SSL cert of another container.

A test has also been added to cover this directive.

[kachkaev]

@lange for now you can use this trick: CERT_NAME= (suggested by @wader). I struggled with the same problem just now and this worked for me like a charm!

[kamermans]

@jwilder This build is failing because Travis-CI is running a newer version of Docker than the one specified in your .travis.yml. We will need to do one of the following:

1. Add --force-yes to the apt-get command to force Travis to downgrade Docker to the version specified (currently 1.12.1-0~trusty)
2. Change the required Docker version to a version that is available on Travis-CI without downgrading
3. Be less specific and just accept whatever version of Docker is available in the testing environment

I think it would be best to do 1 and 2, where we figure out the latest version in Travis, pin that one in .travis.yml and add the --force-yes flag to prevent this from happening in the future.

[jwilder]

This looks good. Can you rebase since #649 has been merged?

[kamermans]

Sure, I'll rebase and push today.

[jwilder]

Thanks @kamermans!