Start work on scalding-lingual support.

Lingual has some nice features that would be nice to have for some small adhoc jobs and especially with the Scalding REPL.  These changes do not contain the repl code yet(coming in a future pull request) but attempt make lingual a bit easier to use with Scalding libraries and allow for scalding code to still be written and run with a Lingual job.

This code also does not support nested functions yet in queries like thrift.  Should be technically possible based on conversations with the Lingual team.


[I am still new to scalding/cascading ] can this work with a TypedPipe/Pipe so that user can easily map fields to produce flattened fields required for Lingual query?