Add support for UNIX socket and named pipe to SELECT INTO OUTFILE 5.6

Registered by Sergei Glushchenko

Allow SELECT INTO OUTFILE/DUMPFILE to be targeted to unix socket or named pipe.
For the case when OUTFILE/DUMPFILE exists and is unix socket or pipe instead of
exit with error, connect to the socket or open the fifo and write output
into it.
Testcase verifies three cases
- regular file exists
- socket exists
- fifo exists

Blueprint information

Status:
Complete
Approver:
None
Priority:
High
Drafter:
Sergei Glushchenko
Direction:
Approved
Assignee:
Sergei Glushchenko
Definition:
Approved
Series goal:
Accepted for 5.6
Implementation:
Implemented
Milestone target:
milestone icon 5.6.13-61.0
Started by
Sergei Glushchenko
Completed by
Laurynas Biveinis

Whiteboard

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Work Items

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