JIRA INFRA-763

Not sure why a tuple instead of network was returned...
There must have been a comma at the end of the line due to copy/pasting
and black converted that to a tuple.

Added a test for the create_interface function.

JIRA INFRA-697 #action In Progress

- create_host doesn't return 403 for user_lab but 200 because the form
  validation fails (the network_id is not part of the form choices)
- caching disabled during tests
  the current_user could sometimes return a different username because of
  caching: the database is cleaned between each test, so different users
  can have the same id and an old user could be returned instead of the new
  one due to caching

JIRA INFRA-578

- add fqdn to host
- add gateway to network
- add netmask to interface
- allow to pass recursive via the API (to expand interfaces in host)
- add is_main property to interface (True if the interface is the main
  interface of the host)

JIRA INFRA-640

JIRA INFRA-578 #action In Progress

- Host names are unique (no 2 hosts with same name)
- A host name shall not conflict with a cname or interface (if not main
interface)
- Interface names are unique (no 2 interfaces with same name)
- An interface shall not conflict with a cname or host (if not assigned
host)
- cnames are only unique by domain (2 cnames can have the same name if
different domains)
- A cname shall not conflict with a host or interface
- An interface has to be linked to a host

Validation is implemented at the model level.
Some is also implemented at the form level as it gives nicer feedback,
but not all as it's a bit more complex when it requires check on several fields.

JIRA INFRA-245

- mac is now a column in the interface table (no link to the mac table)
- mac column is unique (can't have 2 interfaces with the same mac)
- the mac table is kept for the items

JIRA INFRA-639

JIRA INFRA-618 #action In Progress

- switch to server side processing to retrieve network hosts
  (the table started to be bigger and takes time to load)
- add full text search using elasticsearch

Note that only the first IP is displayed in the host table (all
interfaces were displayed before). Search can be performed on any
interfaces.

JIRA INFRA-595 #action In Progress

JIRA INFRA-575 #action In Progress

New get_json method on test client response.
See http://flask.pocoo.org/docs/1.0/testing/#testing-json-apis

https://black.readthedocs.io/en/stable/

Fixes INFRA-197

Allow to keep track of batches of small parts.

Column not visible but searchable.
Allow to search comments and TAG number for items imported from JIRA.

Required to create users when importing items from JIRA.

Renamed blueprint from "users" to "user" to be consistent with other
blueprints (inventory and network).

+ fix tests

Put under the functional directory all tests that require
access to the database. There is a "session" fixture in that
directory that is automatically invoked for each tests. It rollbacks
any transaction after the test to leave the database clean.

Other tests should go under the unit directory.

Inspired from:
- https://stackoverflow.com/a/38626139
- http://alexmic.net/flask-sqlalchemy-pytest/