Fix unknown lastKnownFileType

Fix quotes

Author: Fatme Havaluova

lib/pbxFile.js

@@ -38,6 +38,7 @@ var FILETYPE_BY_EXTENSION = {
         octest: 'wrapper.cfbundle',
         pch: 'sourcecode.c.h',
         plist: 'text.plist.xml',
+        png: "image.png",
         sh: 'text.script.sh',
         swift: 'sourcecode.swift',
         tbd: 'sourcecode.text-based-dylib-definition',

lib/pbxProject.js

@@ -1520,15 +1520,25 @@ function pbxBuildFileObj(file) {
 function pbxFileReferenceObj(file) {
     var fileObject = {
         isa: "PBXFileReference",
-        name: "\"" + file.basename + "\"",
-        path: "\"" + file.path.replace(/\\/g, '/') + "\"",
+        name: file.basename,
+        path: file.path,
         sourceTree: file.sourceTree,
         fileEncoding: file.fileEncoding,
         lastKnownFileType: file.lastKnownFileType,
         explicitFileType: file.explicitFileType,
         includeInIndex: file.includeInIndex
     };
 
+    if(fileObject.name.indexOf("\"") !== -1) {
+        fileObject.name = fileObject.name.replace(/\"/g, "\\\"");
+        fileObject.path = fileObject.path.replace(/\"/g, "\\\"");
+    }
+    
+    if(!file.basename.match(/^[a-zA-Z0-9_\.\$]+\.[a-zA-Z]+$/)) {
+        fileObject.name = "\"" + fileObject.name + "\"";
+        fileObject.path = "\"" + fileObject.path + "\"";
+    }
+
     return fileObject;
 }