pages: browser code, first draft: - code for browser can now be specified if a page subdirectory named `_browser` exists - the default engine used is `Brython` (not yet implemented, so it will do nothing for now) - build_path now uses C.SITE_NAME_DEFAULT for default site instead of empty string, to avoid collision with other sites - ProtectedFile transtype path (first positional argument) to str, so a pathlib.Path can be used

import os.path

version_file = os.path.join(os.path.dirname(__file__), "VERSION")
try:
    with open(version_file) as f:
        __version__ = f.read().strip()
except NotImplementedError:
    # pyjamas workaround
    __version__ = "0.7.0D"