Revert "Use jackson as jar"

This reverts commit 7068a15c4cca8bf1f25369d9167bd8531ddaa140.

Conflicts:
	ruby-gem/lib/calabash-android/helpers.rb
	ruby-gem/test-server/instrumentation-backend/src/sh/calaba/instrumentationbackend/CalabashInstrumentationTestRunner.java
Restore the JSON handling code in NanoHTTPD

HttpServer relies on this for command parsing at the moment.