The names netbox-generated-host and netbox-generated-host-extras didn't
really state why each one was placed where. This commit renames them to
netbox-generated-host-pre and netbox-generated-host-post to indicate
that they are used to allow manual configuration before and after the
generated parts.

Sometimes, hosts don't have a platform configured in NetBox. This commit
handles this case properly by assuming those devices are not Linux
devices.

The NetBox inventory provides a good way to configure which drives are
present in a device and which of them shall be checked with which using
which check script (the latter is done with tags).

This commit updates the information retrieval for smart/smart-sectors
from config context to obtaining a list of inventory items with the tags
monitoring-check-smart and monitoring-check-smart-sectors.

Signed-off-by: Adrian 'nex' Schollmeyer <adrian.schollmeyer@fem.tu-ilmenau.de>

Generating the config with a bunch of string generation is tedious and
not so well to read. Thus, using Jinja2 to create a template and then
just passing the variables is a sensible choice. This commit removes all
string-generating functions and replaces it with Jinja2 templating.

Signed-off-by: Adrian 'nex' Schollmeyer <adrian.schollmeyer@fem.tu-ilmenau.de>

Signed-off-by: Adrian 'nex' Schollmeyer <adrian.schollmeyer@fem.tu-ilmenau.de>

Signed-off-by: Adrian 'nex' Schollmeyer <adrian.schollmeyer@fem.tu-ilmenau.de>

Signed-off-by: Adrian 'nex' Schollmeyer <adrian.schollmeyer@fem.tu-ilmenau.de>

Signed-off-by: Adrian 'nex' Schollmeyer <adrian.schollmeyer@fem.tu-ilmenau.de>

Signed-off-by: Adrian 'nex' Schollmeyer <adrian.schollmeyer@fem.tu-ilmenau.de>

Signed-off-by: Adrian 'nex' Schollmeyer <adrian.schollmeyer@fem.tu-ilmenau.de>