Fixes #4221: Move r30551 to v1.7 branch (add a security framework for authenticating connections)

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r30551 [[BR]]
Add a security framework for authenticating connections - we will add LDAP, Kerberos, and Keystone support in the next month. For now, just put a placeholder "basic" module that does the minimum.

Wire the security check into ORTE's OOB handshake, and add a "version" check to ensure that both ends are from the same ORTE version. If not, report the mismatch and refuse the connection

Fixes #4171

cmr=v1.7.5:reviewer=jsquyres:subject=Add a security framework for authenticating connections


r30554 [[BR]]
Upgrade the security framework to avoid multiple hits against the global security server. Add support for future case where mpirun assings a global security credential for a given run, though we need to work out how to handle connect-accept from other mpirun's in that case. Remove a bunch of duplicate code in the OOB by consolidating the connection handshake code.

Refs #4221


r30704 [[BR]]
Update the keystone sec module - will use curl to connect to server
Fixes #4257: Move r30689 to v1.7 branch (cleanup session directories better)

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r30689 [[BR]]
Do a little better job of cleaning up the session directory left by mpirun by ensuring we delete the event associated with debugger attachment and unlinking the pipe used for that purpose. Also, we no longer leave "abort" files around, so remove that check when deleting session directory trees

cmr=v1.7.5:reviewer=jsquyres:subject=cleanup session directories better
Fixes #4263: Move r30701 to v1.7 branch (Ensure an orted exits with)

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r30701 [[BR]]
Ensure an orted exits with non-zero status if it is unable to send a message. Add more diagnostic messages to the OOB set_addr code

cmr=v1.7.5:reviewer=jsquyres


r30702 [[BR]]
Handle "localhost" better

Refs #4263