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Merge pull request #2623 from phpnode/patch-1

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Distributed: fixed issue #2669
Distributed: fixed problem with creation of hash index
Distributed: fixed issue with synchronization
Fixed issue #2679
Minor: improved output of test sharding testcase
Removed OrientDB shutdown on end of run
Minor: reported the text in error on json parsing
Releasing OrientDB v1.7.8
Merge branch '1.7.8'
Switched to 1.7.9-SNAPSHOT
Fixed issue #2683
Fixed issue #2681
Fixed issue #2684
Fixed issue #1938
Console: in case of ioexception a message it's displayed
Updated ConcurrentSQLBatchUpdateSuperNodeTest test case
Minor: fixed bug on script executor where last result couldn't be taken in case of exception
fix for use of different serializer by the db compare