Fixes layout of Configuration docs
a few tweaks for jenkins debugging
fix logging
update to 2.12.3
Fix MongoUpdateWritable serialization

readFiles would catch an exception during read (INFO  [main]
io.MongoUpdateWritable (MongoUpdateWritable.java:readFields(135)) - No
Length Header available.java.io.EOFException) because write had only
written out the query and not the modifiers as well.
formatting
clear HADOOP_PREFIX before running/starting anything.
we don't need to see that 'export' info everytime
fix log truncation
shutdown cluster after tests
log cleaning
HADOOP-148: Fixes documentation for Pig and various minor inconsistencies in the code
a few tweaks to modernize docs and pass checkstyle
rolling back parameter order changes
slight code clean ups
Merge pull request #110 from lfrancke/fix-config-doc

Fixes layout of Configuration docs
use newer property names
Close DB connection to avoid connection leakage