Add short a greetings/congratulations/next steps text to our build scripts

[suntzu86]

From @sc932:

congrats!
try this
open this
like some text for when it finishes
about the demo and docs and examples
~5-10 lines

The main places to put such text would be:

1. in the main CMakeLists.txt file (see: http://www.cmake.org/cmake/help/v3.0/command/message.html, level none or STATUS makes the most sense)
2. in setup.py, as the last line of InstallCppComponents.run() (this is the last thing that will execute when running python setup.py)
3. in Dockerfile. Not 100% sure where we can put this b/c the last thing the Dockerfile does is launch the webserver. It would be embarrassing to post the 'congrats' message, then have webserver launch fail.

We could have slight modifications of the same base msg (e.g., cmake says congrats C++ is built, points user to C++ demos while docker points user to higher level demos/tutorials)

[sc932]

I am changing this ticket to adding a welcome message to server startup instead of install. The docs are pretty explicit how to install everything and what to do next, the server part has left some users wondering.