function binSearch(arr, value) {
    /* jshint bitwise: false */
    var imin = 0;
    var imax = arr.length - 1;
    while (imin <= imax) {
        var imid = (imin + imax) >>> 1;
        var val = arr[imid];
        if (val === value) {
            return imid;
        } else if (val < value) {
            imin = imid + 1;
        } else { imax = imid - 1; }
    }
    // Not found: return -1-insertion point
    return -imin - 1;
}
Get or create the Layout table (GSUB, GPOS etc).
@param  {boolean} create - Whether to create a new one.
@return {Object} The GSUB or GPOS table.