Minor housecleaning for distributed runtime

- Remove deprecated OP_FileReader
- Make CppResourceInfo an object like ScalaResourceInfo
- Pop stack in Serialization.scala
- Rename requestData methods to be a little clearer
A host of bug fixes, primarily for distributed file writing.

- Added slave information to resourceInfo
- DeliteFileOutputStream fixed to take slave resources into account
- Fix DEG bug with EOP not registering all dependencies
- Add struct alias for data field
- Better error checking for distributed loopBounds calculations and
distributed Foreaches.
- Fixed a MultiLoopSoA bug where matrices were being unsafely unwrapped
in cluster mode.