Add kpact documentation about pact-jvm

[usr42]

Started to write documentation: https://github.com/usr42/pact-jvm/blob/kpact/pact-jvm-consumer-kotlin/README.adoc
asciidoc is not fully supported by Github, so the documentation should probably be split between a brief README.md and the complete asciidoc documentation ad gh-page.
The parsed asciidoc documentation is reachable here: https://usr42.github.io/pact-jvm/

[usr42]

TODO:

• gh-page auto deployment (with travis)
• Markdown README (should contain examples, so maybe auto-generated out of asciidoc; e.g. https://gist.github.com/cheungnj/38becf045654119f96c87db829f1be8e)

[usr42]

Added the brief MD readme and an automatic build and deployment for the asciidoc documentation. To make this possible I had to adapt the .travis.yml which should not be merged back to the upstream. So, only commits to the trigger-travis branch trigger deployments. This is unfortunately a manual step, yet.