Changed some values to be explicitly boolean
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* Added support for ping only devices.
* Renamed sql-schema/206 to 207.
* Discovery tried to detect the OS when it shouldn't.
* Updated db_schema.yaml
* Added ping icon.
* Don't show unused graphs and tabs when SNMP is disabled.
* Allow the user to specify OS of ping only devices.
* Removing custom OS now changes it to 'ping'.
* Removed unnecessary use of mres().
* UI select box for SNMP enable/disable.
* Hide device_ping_perf if ping is disable on device.
* Fixed SNMP settings update status messages.
* Added functionality to add ping only devices via the web ui.
* Added ping only option to addhost.php
* Added ping only support to snmp-scan.py
* Moved sql 208 to 211
* Fixed scrutinizer issues.
* Fixed broken ossearch.
* Added ping only support to the API.
* Updated API doc.
* Added (optional) to OS and hardware description. Hid Port Settings, Applications, Modules, Storage, Processors, Memory and Components from the edit menu
* Style fix.
* Updated ping icon.
* clean() instead of mres(). More escaping. Better help in snmp-scan.py and addhost.php
* Fixed scrutinizer issue.
* Always try SNMP in snmp-scan.py, new option for it in addhost.php. Slice instead of chunk in ajax_ossuggest.php. Other minor style changes.
* Updated sql modifications to insert the new column in the same place as in db_schema.yaml.
