Fixes #4196: Move r30465 to v1.7 branch (do not install mpio.h)

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r30465 [[BR]]
Per http://www.open-mpi.org/community/lists/devel/2014/01/13938.php,
Orion Poplawski noticed that we should not be installing mpio.h.

cmr=v1.7.4:reviewer=hjelmn:subject=do not install mpio.h
Fixes #4194: Move r30462 to v1.7 branch (Fix --without-hwloc builds)

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r30462 [[BR]]
Fix --without-hwloc builds

cmr=v1.7.4:reviewer=jsquyres
Fixes #4191: Move r30449 to v1.7 branch (correct help message)

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r30449 [[BR]]
Ah @$#!$#% - missed one last help message that needs to be corrected.

cmr=v1.7.4:reviewer=jsquyres:subject=correct help message
Fixes #4193: Move r30459 to v1.7 branch (update platform files)

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r30459 [[BR]]
update platform files

cmr=v1.7.4:reviewer=ompi-gk1.7