[18.0][ADD] fleet_telemetry_maps

[douglascstd]

New module fleet_telemetry_maps: map and route views for the telemetry
data provided by fleet_telemetry, based on fleet_maps and
web_view_leaflet_map.

Depends on:

• [18.0][ADD] fleet_telemetry: new module #238 (fleet_telemetry)
• [18.0][ADD] fleet_maps: new module #241 (fleet_maps)

Features

• A map view for fleet.telemetry records, showing the position of each
  received point.
• Route drawing: points are grouped by vehicle and route day and displayed
  as colored polylines.
• A legend in the top right corner to show/hide routes by vehicle and by
  day.
• A Telemetry Map menu entry and the leaflet map view added to the
  telemetry action.
• Sets a sensible default OpenStreetMap tile server in the
  leaflet.tile_url system parameter.

Tests

Unit tests cover the computed map fields, the route colors per day, the
vehicle position computed from telemetry and the data records.

How to test

1. Install fleet_telemetry_maps (with fleet_telemetry records).
2. Go to Fleet > Configuration > Telemetry > Telemetry Map.
3. Routes are drawn per vehicle and day; use the legend to filter.