- Uniform colors and design
- Replace duplicated icons (eg. sale / sale_management)
- Improve misleading icons (eg. POS)
- Add icons for new apps

Add SVG versions to lossless future editing and print/marketing use.

task-54681

This is a simple renaming without adaptation.

The rev. odoo/odoo@93bf26a modifies the way kanban record defines their size.
Kanban dashboards used to define a fixed size and reset it when grouping.
This fixed size should in fact only be set for ungrouped kanban as the column
size is fixed.

* account, maintenance, mrp, payment, point_of_sale, sales_team

Previous system was:
- `flex: 1 1 300px;` on kanban records
- If a specific record needs a different size, add custom style to
  either change the `flex` rule or set a `min-width` for >=SM screens

Now:
- `flex: 1 1 auto;` and `width: 300px;` on kanban records
- If a specific record needs a different size, add custom style to
  change the `width` rule.

This allows some standardization of the way to customize the suited
width and also allow lesser LESS code (as the previous version required
either the use of the flex mixin or the use of a media query).

Note:
- Also remove useless app record rule
- Also fix MRP Work Centers record width

Note2:
This system should be improved for version 12.0.

 - rename models from hr.equipment.something to maintenance.something
 - add concept of maintenance team and dashboard
 - remove generic alias for maintenance

hr_equipment module is renamed to maintenance. No change is performed to the
module itself. It prepares further changes, mainly splitting maintenance from
hr_maintenance.