(#395) Complex Razor Microkernel version numbers not handled properly

Changes made in December of 2012 to handle the more complex version numbers that could be generated by the, at the time, newly revised Microkernel ISO build process led to issues when comparing newer, stable versions of a Microkernel with older, patched versions of the Microkernel.  The code that calculate the weights (from the ISO version number) that are used by Razor to determine which Microkernel ISO to load when booting a node was not calculating these weights correctly.  This change should resolve that issue by calculating the weights as floating point numbers (with the part after the decimal being the commit number and the part before the decimal being an integer representation of the latest tag) instead of comparing these versions as integer numbers (which did not work...older, patched versions were preferred over newer, unpatched versions).