fix for javadoc build target
fix typ in classname: c.f.FLowDescriptors -> c.f.FlowDescriptors
Fixed issue in c.f.h.p.HadoopStepGraph where Traps would be ignored if the Flow had no operation ("copy flows").
Added a new c.t.TupleEntrySchemeIterator property to set certain exceptions to be caught, ignored, and logged during read. Commonly java.io.EOFException is thrown and can be safely ignored. By default no exception will be ignored.
Fixed issue in c.f.h.ProcessFlow where the flowStats object would try to mark a flow as "STOPPED" even if it was already "FINISHED" causing an IllegalStateException.
Added c.m.a.URISanitizer, an implementation of the c.m.a.Sanitizer interface, for sanitizing URIs of different resources (file, HTTP, HDFS, JDBC etc.). c.t.Tap and all subclasses use it for the identifier.
fix null handling problems in URISanitizer.
Fixed issues around c.o.e.ExpressionFunction and c.o.e.ExpressionFilter either accepting Fields.NONE as incoming arguments, or inheriting incoming type information from the resolved arguments.
Transparent DistributedCache support for the rhs source of HashJoin

1. During planning record cascading.tap.hadoop.cached.<tapid>=inputPathCSV
   for hash join tap
   Set the tap source to cdcfs:/<tapid>

2. Prior to submitting FlowStep jobs, check whether DistributedCache needs to be populated
   by inspecting all taps.
   for each original input <pathUri>, create a DC entry
     <pathUri>#<tapid>-cdcfs-<symlinkUUID>

3. On the server side, when mapper calls getSplits on cdcfs:/<tapid>, all
   localized files in DC that match whose symlink matches <tapid>-cdcfs-*
   are returned.

Making DistCache for HashJoin optional
via cascading.distcache.hashjoin. Enabled by default