Compare the installed to required version. Assumes Semantic Versioning.

compareversions.js

   /*
    * Compare the installed to required version.
    *
    * @param {String} installed The currently installed version string.
    * @param {String} required The required version string.
    *
    *   compareVersions('1.0.1', '1.0.0') returns true
    *   compareVersions('1.0.0', '1.0.0') returns true
    *   compareVersions('0.0.9', '1.0.0') returns false
    *   compareVersions('1.0.0', '1.0.1') returns false
    *   compareVersions('2.1.2', '1.1.1') returns true  
    *
    * Returns {Boolean}
    * */
    compareVersions: function (installed, required) {

        var a = installed.split('.');
        var b = required.split('.');

        for (var i = 0; i < a.length; ++i) {
            a[i] = Number(a[i]);
        }
        for (var i = 0; i < b.length; ++i) {
            b[i] = Number(b[i]);
        }
        if (a.length == 2) {
            a[2] = 0;
        }

        if (a[0] > b[0]) return true;
        if (a[0] < b[0]) return false;

        if (a[1] > b[1]) return true;
        if (a[1] < b[1]) return false;

        if (a[2] > b[2]) return true;
        if (a[2] < b[2]) return false;

        return true;
    }