[TIMOB-3516] Android: density-specific splash screen not working on Windows

It's currently impossible to use density-specific splash screens on Android when building on Windows. The bug is easy to fix; in the following code from support/android/builder.py:

     # look for density-specific default.png's first
        if os.path.exists(android_images_dir):
            pattern = r'/android/images/(high|medium|low|res-[^/]+)/default.png'
            for root, dirs, files in os.walk(android_images_dir):
                for f in files:
                    path = os.path.join(root, f)
                    if re.search(pattern, path):
                        res_folder = resource_drawable_folder(path)
                        debug('found %s splash screen at %s' % (res_folder, path))
                        dest_path = os.path.join(self.res_dir, res_folder)
                        dest_file = os.path.join(dest_path, 'background.png')
                        if not os.path.exists(dest_path):
                            os.makedirs(dest_path)
                        shutil.copy(path, dest_file)

change "if re.search(pattern, path):" to "if re.search(pattern, path.replace("\", "/")):"

It might be good to audit the rest of the code too for this problem.