export more generic version of TaskDao::updateTask() through TaskManager
CORE: added refreshSession(sess) method

- Added method for refreshing user and authz in session.
  It's for case, when user join identities and we want
  to get new user into session, without whole logout/login.

- Added javadoc for refreshAuthz(sess) metod.
Fix javadoc in RPC

 - problem with javadoc on SearcherMethod.java
Merge pull request #539 from stavamichal/fixInRpcJavadoc

Fix javadoc in RPC
Merge pull request #538 from zlamalp/core

CORE: added refreshSession(sess) method