Add new side menu bar to the server

When the super-awesome top-level menu prototype is finished, add it to zanata-server to replace the existing menu.

Does not include implementing all prototyped features, just:

• add as menu template to replace existing menu template

• search: projects, people, languages (language teams), groups

• level of testing:

  • unit test all the React components

  • functional tests for the integration with the search API