Introducing support for internal SSL communication.

Secured corporate landscapes may require that communication traffic be encrypted. So we have prepared a change, which makes internal traffic go over SSL, where appropriate. For these purposes:

- suitable SSL certificates must be generated and provided as new configuration properties
- a java keystore file must be provided inside tomcat/conf. We have included a simple and dummy one
- an HTTPS connector in Tomcat must be enabled. The keystore password is "cloudfoundry".
- the nginx servers must be recompiled against the OpenSSL library, and several other nginx modules/plugins.
- we have adopted the strategy of using a nginx server in front of the cloud controller, having opened both plain HTTP and HTTPS servers.


Note: This change is relevant for Tomcat-powered applications only.


Important: Detailed user guide documentation for this change can be found here: https://github.com/cloudfoundry-collaboration/vcap/wiki/Setup-internal-SSL-communicationDear Cloud Foundry contributor,

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Recently we made some changes in how we are verifying and reviewing open source
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Follow these steps to make a contribution to any of our open source
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1. Complete our CLA Agreement for
   [individuals](http://www.cloudfoundry.org/individualcontribution.pdf) or
   [corporations](http://www.cloudfoundry.org/corpcontribution.pdf).
1. Sign up for an account on our public Gerrit server at
   http://reviews.cloudfoundry.org/.
1. Create and upload your public SSH key in your Gerrit account profile.
1. Set your name and email:

                git config --global user.name "Firstname Lastname"
                git config --global user.email "your_email@youremail.com"

1. Install our gerrit-cli gem:

                gem install gerrit-cli

1. Clone the Cloud Foundry repo:
   _Note: to clone the BOSH repo, or the Documentation repo, replace
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                gerrit clone ssh://reviews.cloudfoundry.org:29418/vcap
                cd vcap

1. Make your changes, commit, and push to gerrit:

                git commit
                gerrit push

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Once your commits are approved by our Continuous Integration Bot (CI Bot) as
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recommend squashing your commit with the original change-id. See the squashing
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