core (memory/disco): fixed types of disco extensions: typeCheck() is not automatically called on reception by Wokkel, as a result extensions fields values may be strings instead of the field type. TypeCheck is now explicitly called in memory.disco to avoid that. It is not called immediately on reception as the string value is needed to calculate the capability hash

# XXX: the Monkey Patch is here and not in src/__init__ to avoir issues with pyjamas compilation
# TODO: remove this when changes are merged in Wokkel
from sat_tmp.wokkel import install
install()