Bug fix - corrected detection of relative paths in import function.

Original check was using "path.sep" (which is undefined) instead of "Path.sep".  Also, the check failed to catch absolute paths in Windows when the path starts with a drive letter (ex. "C:\folder\file.js").

lib/sequelize.js

@@ -280,7 +280,7 @@ module.exports = (function() {
 
   Sequelize.prototype.import = function(path) {
     // is it a relative path?
-    if (Path.normalize(path).indexOf(path.sep) !== 0) {
+    if(Path.normalize(path) !== Path.resolve(path)){
       // make path relative to the caller
       var callerFilename = Utils.stack()[1].getFileName()
         , callerPath     = Path.dirname(callerFilename)