Updated `.travis.yml': whitelist git-flow branches
Updated `README.md': travis-ci git-flow branches
Updated `module/dns': may fix nima/site#23

Fix can only be confirmed on Travis CI as I can't reproduce the
problem locally at all.
Speed up RNG with `haveged': entropy on steroids
Cleanup `extern': closes nima/site#26
Updated `.travis.yml': enhance, fix

Enhance:

    Stronger integration between travis and citm script.

Fixes:

    Fixed `branches.only' regex.

Updates:

    The `volatile' branch is back, sometimes it is still helpful to
    have this branch around rather than commit changes to develop.
Multi-profile support; closes nima/site#28

It is now possible to have and switch between multiple profiles;
SITE_PROFILE is no longer used, instead a user utility (bin/activate)
has been introduced which allows you to create and switch between
various profiles.

In addition to this, the profile area has been moved out of the
site-specific VCS space and into `~/.site/profiles.d/'.

General house-keeping in `libsite.sh'.
Fixed `module/net'
Updated `module/vault': fix, enhanced
Updated `tests/remote'

Gracefully handle remote:copy failures for now (for whatever reason,
the test amended fails intermittently on Travic-CI).