Dockerize simulator and example connectors

[mkorszun]

This should simplify setup of the local development environment while building tableau WDC.

Instead of cloning and building it locally, with this simple Dockerfile we can bootstrap everything required in just two steps:

docker build . -t webdataconnector
docker run -d -p 9999:8888 webdataconnector:latest

And access simulator at: http://localhost:9999/Simulator/index.html

or examples at: http://localhost:9999/Examples/

Would be also recommended that Tableau builds and publishes this container to one of the public docker reposiotories (i.e. DockerHub).

[coveralls]

Coverage remained the same at 98.913% when pulling 3d8e6147000416e66b83f5501825e8d8333e4544 on mkorszun:dockerize-simulator into c7dad897bc745ec9b20b806f6163a749b403ba55 on tableau:master.