Create detailed instructions for building MercuryDB and running through the example

[dilijev]

Currently it is not clear how to bootstrap the source package which depends on the MercuryDB library (Index annotation). Is it possible to use the same JAR as a reference instead of as an application? (I think so.)

The fact that it has an entry point should only matter when running it with

java -jar mercurydb.jar <source> <dest>

We should provide a script and patch instructions into the README to explain how to run through the example. It is good that we are showing the resulting code, but it would be nice to allow users to verify this for themselves.

[dilijev]

The build script and examples are great but we need documentation so that someone can walk through the process on their own.