Fix #103: numberofcores giving bad output.

A previous change added nproc as a fallback, but nproc's output icnludes
a newline. This removes the newline and prints "unknown" as a last
resort.
Specify full path to nproc.
fixes some bugs on speed.php
Merge pull request #133 from gliderShip/master

fixes some bugs on speed.php
Merge pull request #131 from afaqurk/nproc

Clean up numberofcores' output