Add JSON support and domain objects, update pom dependencies and some refactoring

[matth]

Update pom.xml dependencies

• maven-scala-plugin is deprecated in favour of maven.scala-maven-plugin
• scala-tools.org repo is deprecated in favour of oss.sonatype.org
• Remove maven-compiler-plugin
• Remove commons-lang
• Add maven-scalatest-plugin
• Add maven-resources-plugin
• Add net.liftweb.lift-json
• Add ch.qos.logback.logback-classic
• Add com.sun.jersey.jersey-client (test scope only)

  Refactor Server and Lookup Resource code

• Server now returns application/json with correct Accept header
• Server port configurable via a system property
• Make the legacy .asmx part of the URL optional
• Refactor LookupResource to remove duplication and take more advantage of jersey's dependency injection
• Decouple relationship between LookupResource and Server object (using DI provider, now no need to call Server.searcher)

  Extend Result domain objects

I have extended the object graph returned by the Searcher, this now models concepts such as Categories, OntologyClasses, etc as Scala objects rather than Strings. This was useful as I have started using the lookup codebase from other Scala projects and allows for better interaction with the data.

• src/main/scala/org/dbpedia/lookup/entities/Entities.scala
• src/test/scala/org/dbpedia/lookup/entities/EntitiesTest.scala

  Refactor Result XML serialization and add JSON serialization

I refactored the XML serialization to use Scala's built in XML handling. This is type safe and compiler checked so less error prone. It also removes the need for the commons-lang dependency. I have also added JSON serialization via the lift-web json library.

• src/main/scala/org/dbpedia/lookup/entities/EntitiesSerialization.scala
• src/test/scala/org/dbpedia/lookup/entities/EntitiesSerializationTest.scala

  Add Scala test

I have added a couple of unit / integration test scenarios. The most useful is probably the full integration test which starts with some raw ntriples, builds a small index then uses the Jersey client over HTTP to interogate an embedded server.

• src/test/scala/org/dbpedia/lookup/IntegrationTest.scala

  Add logging via Logback

I replaced the System.err.println calls with a Logback logger which should be more configurable to a user's preference

[pablomendes]

@maxjakob I read through the code. This looks like a superb contribution to me. I am itching to merge.

I just want to give you a chance to look over it, as you know the code much better than me.

[maxjakob]

Fantastic! :metal: Gave @matth push rights to this repo.

[pablomendes]

:+1:

[matth]

Thanks a lot guys!