Update synchronized decorator so that it can be used as a context manager for synchronized statements.
Update synchronized decorator so that it can be used as a context manager for synchronized statements.

linglaiyao1314/wrapt,GrahamDumpleton/wrapt,akash1808/wrapt,pombredanne/python-lazy-object-proxy,GrahamDumpleton/wrapt,pombredanne/wrapt,wujuguang/wrapt,ionelmc/python-lazy-object-proxy,pombredanne/python-lazy-object-proxy,pombredanne/wrapt,linglaiyao1314/wrapt,github4ry/wrapt,ionelmc/python-lazy-object-proxy,github4ry/wrapt,wujuguang/wrapt,akash1808/wrapt