Remove timeouts from remote communication loop.

The select() now blocks until there's work to do instead of relying on a
small timeout value which can cause unproductive use of cpu cycles.
Merge branch 'master' into topic/jsiwek/improve_comm_loop
Fix possible abort on writing to a full pipe.
Fix Pipe copy/assignment to make a copy of flags.
Merge branch 'master' into topic/jsiwek/improve_comm_loop

Conflicts:
	src/CMakeLists.txt
	src/FlowSrc.cc
	src/FlowSrc.h
	src/IOSource.h
	src/PktSrc.cc
	src/PktSrc.h
	src/iosource/Manager.cc
Add a simple FD_Set wrapper/helper class.
Improve error message when failing to activate a plugin.

Also fix a unit test helper script that checks plugin availability.
Merge remote-tracking branch 'origin/topic/jsiwek/missing-plugin'

* origin/topic/jsiwek/missing-plugin:
  Improve error message when failing to activate a plugin.

BIT-1252 #merged
Merge remote-tracking branch 'origin/topic/jsiwek/improve_comm_loop'

* origin/topic/jsiwek/improve_comm_loop:
  Add a simple FD_Set wrapper/helper class.
  Fix Pipe copy/assignment to make a copy of flags.
  Fix possible abort on writing to a full pipe.
  Remove timeouts from remote communication loop.
Updating submodule(s).

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Updating submodule(s).

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Updating submodule(s).

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