Feature Request: Add Perfdata for accesspoint-status

[bickhorn]

Hello,

First, thank you for this wonderful plugin !

Is it possible to add some perfdata to the mode accesspoint-status ?

For now it is fully textual :

./check_nwc_health --community XXX --hostname 10.X.X.X --mode  accesspoint-status
OK - access point BW-A221 is enable/associated (2 interfaces with 6 clients), access point BW-B223 is enable/associated (2 interfaces with 2 clients)

Would it be possible to have for exemple :

./check_nwc_health --community XXX --hostname 10.X.X.X --mode  accesspoint-status
OK - access point BW-A221 is enable/associated (2 interfaces with 6 clients), access point BW-B223 is enable/associated (2 interfaces with 2 clients) 
| 'BW-A221_clients'=6 'BW-B223_clients'=2

End even maybe add some warning if too much client are on an access-point ?

Best regards