Error monitor: Give GSA sync more retries on conflicts

Note: Paul (me) is just guessing on this. Below is a traceback produced by gsa_sync. It doesn't happen frequently, but in the interests of "shut up error monitor", perhaps we can give it more retries or something.

Error in script.

Traceback (most recent call last):
  File "/srv/osfkarl/production/14/eggs/karlserve-1.20-py2.6.egg/karlserve/scripts/main.py", line 201, in wrapper
    return func(args)
  File "/srv/osfkarl/production/14/eggs/osi-3.46-py2.6.egg/osi/scripts/gsa_sync.py", line 57, in main
    transaction.commit()
  File "/srv/osfkarl/production/14/eggs/transaction-1.1.1-py2.6.egg/transaction/_manager.py", line 89, in commit
    return self.get().commit()
  File "/srv/osfkarl/production/14/eggs/transaction-1.1.1-py2.6.egg/transaction/_transaction.py", line 329, in commit
    self._commitResources()
  File "/srv/osfkarl/production/14/eggs/transaction-1.1.1-py2.6.egg/transaction/_transaction.py", line 446, in _commitResources
    rm.tpc_vote(self)
  File "/srv/osfkarl/production/14/eggs/ZODB3-3.10.5_perfmetrics-py2.6-linux-i686.egg/ZODB/Connection.py", line 781, in tpc_vote
    s = vote(transaction)
  File "/srv/osfkarl/production/14/eggs/perfmetrics-1.0-py2.6.egg/perfmetrics/__init__.py", line 120, in call_with_metric
    return f(*args, **kw)
  File "/srv/osfkarl/production/14/eggs/RelStorage-1.5.1_perfmetrics2-py2.6.egg/relstorage/storage.py", line 797, in tpc_vote
    return self._vote()
  File "/srv/osfkarl/production/14/eggs/RelStorage-1.5.1_perfmetrics2-py2.6.egg/relstorage/storage.py", line 844, in _vote
    serials = self._finish_store()
  File "/srv/osfkarl/production/14/eggs/RelStorage-1.5.1_perfmetrics2-py2.6.egg/relstorage/storage.py", line 756, in _finish_store
    rdata = self.tryToResolveConflict(oid, prev_tid, serial, data)
  File "/srv/osfkarl/production/14/eggs/ZODB3-3.10.5_perfmetrics-py2.6-linux-i686.egg/ZODB/ConflictResolution.py", line 277, in tryToResolveConflict
    data=newpickle)
ConflictError: database conflict error (oid 0x024506c6, class BTrees.IOBTree.IOBucket, serial this txn started with 0x039debaa78725baa 2013-04-11 16:10:28.229698, serial currently committed 0x039debb11fef3877 2013-04-11 16:17:07.484638)