incorrect handling of commit/ignore error in unique index code


ndb/src/kernel/blocks/dbtc/DbtcMain.cpp:
  1) handle potential ptr error
  2) remove incorrect commit-handling in uk code
ndb/src/ndbapi/NdbTransaction.cpp:
  1) force 4012
  2) handle AO_IgnoreError in uk code
ndb/src/ndbapi/Ndbif.cpp:
  force 4012
ndb/test/ndbapi/testIndex.cpp:
  test program for 25059
ndb/test/run-test/daily-basic-tests.txt:
  add testcase