remove IntelliJ meta-data that shouldn't be tracked

the .idea directory is already in .gitignore, these files were probably accidently checked in before .gitignore was created
hide filters API implementation details a bit
use an older version of maven-jar-plugin

fixes this error in Eclipse:
https://github.com/tesla/m2eclipse-extras/issues/10#issue-3294209
make the apiUrl the root api url

the endpoint name won't change between instances, and it makes it easier to dynamically configure the api URL for multiple endpoints
refactor POJO marshaling/unmarshaling to cleanly handle wrapper json nodes
Convert `EntitySearchResponse` to extend guava's `ForwardingList`.
 - check search endpoint for error responses
 - use `Throwables.propogate()` to gracefully throw JSON exceptions, instead of a 500 `WebApplicationException` which is misleading.
Merge pull request #11 from CruGlobal/dev

Dev