Launchpad fixes_2

-- hbase access errors were not being returned during process bringup phase.
  arkcmp/CmpContext.*, bin/SqlciErrors.txt
  sqlcomp/CmpSeabaseDDLcommon.cpp, CmpSeabaseDDLtable.cpp, nadefaults.cpp
  launchpad #1343061

-- showddl now shows hbase options, salted partitions.
-- hbase_options and salt info is kept in metadata.
  comexe/ComTdb.h, optimizer/NATable.cpp, NATable.h
  parser/sqlparser.y
  sqlcat/desc.h, sqlcomp/CmpDescribe.cpp, CmpSeabaseDDLcommon.cpp
  CmpSeabaseDDL.h, CmpSeabaseDDLTable.cpp
  launchpad #1342465
  launchpad #1342996

-- added support for update where current of cursor.
  generator/GenRelScan.cpp, GenRelUpdate.cpp,
  launchpad #1324679

-- check constrs in update and views
  generator/GenRelUpdate.cpp, optimizer/BindRelExpr.cpp
  Launchpad #1320034, #1321479

-- long column name returned assertion.
  optimizer/ObjectNames.cpp
  launchpad #1324689

-- purgedata does not recreate with the original salt and hbase options.
  optimizer/RelExeUtil.cpp, sqlcomp/CmpSeabaseDDLcommon.cpp
  launchpad #1322400

-- long keys got assertion failure:
  optimizer/ValueDesc.cpp
  launchpad #1332607

-- cqd hide_indexes was causing constraint creation to fail.
  sqlcomp/CmpSeabaseDDLcommon.cpp
  launchpad #1340385

-- current_timestamp/time functions are now non-nullable.

Change-Id: Ib3a071894d11d0e3719b98f0cfddfc5ce8624519