pages: identities are not using `data_objects` anymore: - identities are now handler directly with the dict received from backend, without using a specific data object. - a new `fillMissingIdentities` method in `LiberivaPage` will help to get all needed identities before rendering the template, and to avoid missing avatar or nickname. - (blog/view): fill missing identities for main blog items, not only for comments

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"