The buttons should only be created if the items_table exists

JIRA INFRA-584

Retrieving all items from the database takes some time.
The task is thus handled by the RQ worker.
We use ajax to periodically monitor the status of the job
and redirect to the file when ready.
A progress bar is displayed to let the user see the progress.

The mechanism put in place could be re-used for other use cases.

JIRA INFRA-545 #action In Progress

JIRA INFRA-545

Included libraries:
- DataTables 1.10.18 (with bootstrap 4 theme)
- Buttons 1.5.2
- Column visibility 1.5.2
- Print view 1.5.2

JIRA INFRA-545

This is not directly supported by CodeMirror.
See https://github.com/codemirror/CodeMirror/issues/850

Add cm-resize library from https://github.com/Sphinxxxx/cm-resize

JIRA INFRA-543 #action In Progress

The official flask-bootstrap is still not compatible with bootstrap 4.
The application basically only uses the main template and one macro.
It's easier to include directly bootstrap in CSEntry.
It makes upgrading to the latest bootstrap much easier and removes a
dependency.

Update to bootstrap 4.1.3

Added:
- jquery-3.3.1.min.js
- bootstrap.bundle.min.js (include popper but not jquery)

Note that jquery.slim can't be used.
We need for example $.getJSON for datatables.

JIRA INFRA-412

Allow to enter Ansible variables on host in YAML format.
Use codemirror (http://codemirror.net) to make editing YAML easier.

JIRA INFRA-412

+ yaml mode

Allow to display tasks

JIRA INFRA-403

JIRA INFRA-302

This is to be used for stack of switches only

- a stack_member is linked to an host (device_type has to be "Switch")
- a stack_member is an integer between 0 and 9 (included) or can be None
- the couple (host_id, stack_member) must be unique

JIRA INFRA-267

- rename "Virtual" to "Virtual Machine"
- add "Virtual IOC"
- add several physical devices (Switch, Industrial PC IOC, MicroTCA,
  VME, PLC)

1. When we have a stack of switches, the same IP is associated to several
   switches
2. Move the items <-> host assocation to the item create/edit page

JIRA INFRA-267

The interface name doesn't need to be displayed in the form as we force
it to the hostname.

We set the interface name to the hostname when submitting the form.
This fixes the copy/paste issue with the mouse that didn't trigger the
keyup event.

JIRA INFRA-287

JIRA INFRA-281

If an error is raised when submitting the form, we should keep the IP
that was entered.

JIRA INFRA-285

The class "is-invalid" is removed on all type=text input
on keyup event.

JIRA INFRA-285

- create many-to-many relationships between the user table and
attributes tables (manufacturer / model / location / status / action)
- add a checkbox as the first column of the attributes table to add or
remove an attribute to the favorites
- add a new page to display the favorite attributes

JIRA INFRA-283

On page load we have to check the machine type to enable / disable
item_id and check / uncheck the random MAC

"type" field on host replaced with foreign key "machine_type_id"

JIRA INFRA-281

If we scroll to the submit button, we can't see the "Submit" QRCode

The QRCode content doesn't matter. It's only there to trigger a CR to
submit the form.
Scanning a serial number will focus on the submit button so that
scanning the QRCode doesn't enter text in any form input field.

- Remove QRcodes page
- Add Status to attributes page (only allow admin to add new statuses)

Actions QR Codes not visible anymore. Required ones shall be put on the
page where they are used.

The network range defines the IP to be allocated.
This is to reserve some specific addresses (for gateway for example).

An admin user should be able to define an interface outside the network
range.

The IP address select field was replaced with a string field
(initialized to the first available IP).

Fixes INFRA-200

Fixes INFRA-197

The interface name shall start with the hostname of the host it is
associated to.

Note that this is only enforced via the UI (from which most users will interact),
not from the API.

Fixes INFRA-195

- add domain_id on NetworkScope table to define a default domain
- add domain_id on Network (default to the Network Scope one)

Fixes INFRA-194

We don't want to submit the form when scanning a code bar or ICS id.
In keyboard mode, the scanner sends a CR as last character.

Allow to use a scanner configured as keyboard to register items
via the web UI.
1. The attributes should be selected manually
2. Focus set manually on ICS id
3. Scan an ICS id -> prefix removed and focus set to serial number
4. Scan serial number
5. Click on submit
6. Focus set automatically on ICS id
7. Repeat from 3

Allow to keep track of batches of small parts.