(ios) Plist document not indented with tabs

Xcode indents .plist documents with tabs, not spaces. Other parts of
Cordova already use tabs for indenting .plist documents and using spaces
directly conflicts with both cases.
diff --git a/spec/ConfigChanges/ConfigChanges.spec.js b/spec/ConfigChanges/ConfigChanges.spec.js
index 657ccf8..e76eab8 100644
--- a/spec/ConfigChanges/ConfigChanges.spec.js
+++ b/spec/ConfigChanges/ConfigChanges.spec.js
@@ -495,7 +495,7 @@
                     var platformJson = PlatformJson.load(plugins_dir, 'ios');
                     platformJson.addInstalledPluginToPrepareQueue('com.adobe.vars', {});
                     configChanges.process(plugins_dir, temp, 'ios', platformJson, pluginInfoProvider);
-                    expect(fs.readFileSync(path.join(temp, 'SampleApp', 'SampleApp-Info.plist'), 'utf-8')).toMatch(/<key>APluginNode<\/key>\n {4}<string\/>/m);
+                    expect(fs.readFileSync(path.join(temp, 'SampleApp', 'SampleApp-Info.plist'), 'utf-8')).toMatch(/<key>APluginNode<\/key>\n\t<string\/>/m);
                 });
                 it('Test 024 : should merge dictionaries and arrays, removing duplicates', function () {
                     fs.copySync(ios_config_xml, temp);
diff --git a/spec/fixtures/projects/ios-config-xml/SampleApp/SampleApp-Info.plist b/spec/fixtures/projects/ios-config-xml/SampleApp/SampleApp-Info.plist
index 22edad6..5ede567 100644
--- a/spec/fixtures/projects/ios-config-xml/SampleApp/SampleApp-Info.plist
+++ b/spec/fixtures/projects/ios-config-xml/SampleApp/SampleApp-Info.plist
@@ -28,10 +28,10 @@
 		<dict>
 			<key>CFBundleIconFiles</key>
 			<array>
-                <string>icon.png</string>
-                <string>icon@2x.png</string>
-                <string>icon-72.png</string>
-                <string>icon-72@2x.png</string>
+				<string>icon.png</string>
+				<string>icon@2x.png</string>
+				<string>icon-72.png</string>
+				<string>icon-72@2x.png</string>
 			</array>
 			<key>UIPrerenderedIcon</key>
 			<false/>
diff --git a/src/ConfigChanges/ConfigFile.js b/src/ConfigChanges/ConfigFile.js
index 151e9b0..be8f78e 100644
--- a/src/ConfigChanges/ConfigFile.js
+++ b/src/ConfigChanges/ConfigFile.js
@@ -94,7 +94,7 @@
     } else {
         // plist
         var regExp = new RegExp('<string>[ \t\r\n]+?</string>', 'g');
-        fs.writeFileSync(self.filepath, modules.plist.build(self.data).replace(regExp, '<string></string>'));
+        fs.writeFileSync(self.filepath, modules.plist.build(self.data, { indent: '\t', offset: -1 }).replace(regExp, '<string></string>'));
     }
     self.is_changed = false;
 };