Implements the rest of network CRUD operations.

Fix ODP-39
Addressed Duarte's concerns on synchronization, etc.
Addressed Duarte's concerns on synchronization, etc.
Merge branch 'dev/tomohiko/odp-39-network-crud/20140109' of github.com:midokura/odp-controller into dev/tomohiko/odp-39-network-crud/20140109
Removed a local var for DataClient in a NetworkAware implementation.
Merge pull request #13 from midokura/dev/tomohiko/odp-39-network-crud/20140109

Implements the rest of network CRUD operations.