Fixes #3764: Move r29157 to v1.7 branch (check for negative np)

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r29157 [[BR]]
Check for bozo error of negative np for an app as this will cause ORTE to spin forever.

cmr:v1.7.3:reviewer=jsquyres:subject=Check for negative np
cmr:v1.6.6:reviewer=jsquyres:subject=Check for negative np
Fixes #3762: Move r29152 to v1.7 branch (Correctly handle list of cores)

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r29152 [[BR]]
Correctly handle list of cores specified in the rankfile - i.e., a rankfile entry such as:

rank 0=foo slot=0:0-1;1:0,1

cmr:v1.7.3:reviewer=jsquyres