# Compares two string versions, and returns -1, 0 or 1, according to the "<=>"
# operator conventions
def version_cmp(version_a, version_b)
    version_a.split(/\./).zip(version_b.split(/\./)) do |a,b|
        return -1 if a.nil?
        return  1 if b.nil?
        return a.to_i <=> b.to_i if (a.to_i <=> b.to_i) != 0
    end
    # Just in case there's any characters
    return version_a <=> version_b
end