New: Added menu Create Project... in xCodeCapp

Previously it wasn't possible to create a capp project from xCodeCapp.
Now you can create one from the menu item Create Project, xCodeCapp will load the project as the same time is no error occurs.
When choosing an existing project, xCodeCapp removes the old one (this is asked to the user, would you like to replace the files...).
In case of errors, the errors panel appears.