pbxFile: Replace "lastType" with "lastKnownFileType" property.

Author: sidneys

lib/pbxFile.js

@@ -149,7 +149,7 @@ function defaultGroup(fileRef) {
 function pbxFile(filepath, opt) {
     var opt = opt || {};
 
-    this.lastType = opt.lastType || detectLastType(filepath);
+    this.lastKnownFileType = opt.lastKnownFileType || detectType(filepath);
 
     // for custom frameworks
     if (opt.customFramework == true) {