The tls_* parameters are not present in Zabbix Server versions prior to
3.0. Thus the API response does not contain these keys and the
zabbix_host module failed. This commit adds checks if the parameters are
present in the API response and otherwise just completely ignores these
parameters. The documentation already states that they are not supported
for Zabbix Server versions below 3.0.
* add checking of interfaces, providing defaults or errors if required keys are not defined
* fix so that iteration of interfaces only happens if defined
* Update zabbix_host documentation (extend ipmi_-documentation, and update style to be consistent on the rest while we are at it)
* Remove ipmi_parameters being added to the API call when not required
* remove optional parameters from add_host, as well
* reorder interfaces handling for force=no, making sure it works when no interfaces are specified in the module parameters
when no interfaces are specified on update, use existing interfaces obtained from API.
check whether visible_name is set in check_all_properties; if not set as module parameter, no comparison is necessary.
Check if description is set as module parameter before comparing as well
* link_templates need the same treatment
* add inventory update checks and simplify update procedure
* make specifying proxy optional on update (keeping it as is when not specified), as well
* pep8 fixes
* add tls_*-checks for updates and make tls_*-options actually optional
Selivanov Pavel
Gaudenz Steinlin
Dag Wieers
Richlv
Eike Frost
Kirill German