Upgrade kiama to 1.5.1.

This version of kiama fixes #279.
improved the exception message when failing on instantiating a constructor or calling a method in the compatibility class
adding a logging message to know when cdh3 or cdh4 is detected by the compatibility class
fixed a compilation error with the previous commit
adding more logging to the Compatibility object
Fix ScoobiConfiguration Mode (do not use Enumeration)
checking the input channel spec
used a snippet for the wordcount example in the README
updated the specs2 dependency
refactored the input and output channels
fixed the optimisation for text file outputs when no bridgestore is necessary
Tidy a use of null
added the current class loader for creating runtime classes
otherwise running in sbt with fork := false fails to get java.lang.String
passing the new MscrsDefinitionSpec
Extraneous code
Merge branch 'master' of github.com:tonymorris/scoobi
Thanks null. You're the best
Make BridgeStoreIterator lazy.

Fix BridgeStoreIterator to construct SequenceFileReader objects lazily
using a Stream. Fixes #285.

BridgeStoreIterator constructs multiple SequenceFileReader objects under
the hood for each part file underlying a materialised DList. These
objects are constructed eagerly and consume file descriptors (socket
connections to HDFS). If the number of part files exhausts the available
file descriptors for the client-side Scoobi process, bad things ensure.

Add a Spec that without this fix shoud fail in cluster mode (but will
still pass in in-memory and local mode).
fixed the persist spec and merged with master
#HADOOP-9746 issue workaround
fixed the persist spec bug in inmemory mode