Move rcdb_web to rcdb library

[DraTeots]

There are several reasons for this:

• Currently to deploy website one has to add $RCDB_HOME/python to PYTHONPATH to find rcdb library and whole $RCDB_HOME to get rcdb_web as a packet. That is weird and may be insecure.
• rcdb_web is a part of RCDB python and should live with the rest of python code
• Being a part of rcdb library, allows web interface to be used (later) in a commands like 'rcdb gui'