Revision 567308

HADOOP-1730 unexpected null value causes META scanner to exit (silently)

Added handling for legal null value scanning META table and added
logging of unexpected exceptions that arise scanning.

M src/contrib/hbase/src/test/org/apache/hadoop/hbase/TestSplit.java
    Refactored to do a staged removal of daughter references.
    (compact, recalibrate): Added.
    (getSplitParent): Refactored as getSplitParentInfo.
M  src/contrib/hbase/src/java/org/apache/hadoop/hbase/HConnectionManager.java
    Added formatting of the find table result string so shorter
    (when 30-odd regions fills page with its output).
M  src/contrib/hbase/src/java/org/apache/hadoop/hbase/HTable.java
    Formatting to clean eclipse warnings.
M src/contrib/hbase/src/java/org/apache/hadoop/hbase/HMaster.java
    The split column in a parent meta table entry can be null (Happens
    if a daughter split no longer has references -- it removes its
    entry from parent).  Add handling and clean up around split
    management code.  Added logging of unexpected exceptions
    scanning a region.
M  src/contrib/hbase/src/java/org/apache/hadoop/hbase/HRegion.java
    Added fix for NPE when client asks for scanner but passes
    non-existent columns.
M src/contrib/hbase/src/java/org/apache/hadoop/hbase/util/Writables.java
    (getHRegionInfo, getHRegionInfoOrNull): Added.: