add @2x versions of menu bar icon

ZeroTier One/Assets.xcassets/MenuBarIconMac.imageset/Contents.json

@@ -7,6 +7,7 @@
     },
     {
       "idiom" : "mac",
+      "filename" : "[email protected]",
       "scale" : "2x"
     }
   ],

ZeroTier One/Assets.xcassets/MenuBarIconMacWhite.imageset/Contents.json

@@ -7,6 +7,7 @@
     },
     {
       "idiom" : "mac",
+      "filename" : "[email protected]",
       "scale" : "2x"
     }
   ],

ZeroTier One/Info.plist

@@ -21,7 +21,7 @@
 	<key>CFBundleSignature</key>
 	<string>????</string>
 	<key>CFBundleVersion</key>
-	<string>13</string>
+	<string>14</string>
 	<key>LSMinimumSystemVersion</key>
 	<string>$(MACOSX_DEPLOYMENT_TARGET)</string>
 	<key>LSUIElement</key>