Removed expandos of built-in Math object; dropped Math.sgn() entirely;
moved Math.uuid() to newly introduced vxJS.math namespace

Change-Id: Id71d8763f624058a4b0df791f09849b90c12ec42
Removed dependency on Math.uuid()

Change-Id: I38dd54ac79e58941f17458c67f4a98fcc268218a
Initial commit of vxJS.math; provides vxJS.math.md5() and
vxJS.math.uuid()

Change-Id: I1328ae252e3dc02691820b966c204a27981616df