* Update showconfig.inc.php
Fix display for pfsense config files.
* Update showconfig.inc.php
Change from else if to elseif
* Update showconfig.inc.php
Decode special chars before syntax highlighting.
* Update pfsense.yaml
* Add config_highlighting device property
Add config_highlighting to device definition
Update showconfig.inc.php to use config_highlighting to set language.
* Update showconfig.inc.php
Fix incorrect code. Chose correct variable where config_highlighting is set.
* Update os_schema.json
Add property config_highlighting to schema
- used for language highlighting when displaying the config file
* Update showconfig.inc.php
Changed some values to be explicitly boolean
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brownowskiandTony Murray
