2016-04-03 : rewrite the original cmk check
2016-05-24 : added admin/operational state, fix for missing ap_name parameter
2016-07-01 : added long output
2016-07-06 : fixed: missing ap
2018-01-05 : cosmetic changes, added metrics/cisco_wlc.py
2018-05-23 : changed scan function, changed return values to yield
             code cleanup, removed unused oid's
2018-07-26 : added code for incomplete ap data (missing lwap, data)
2018-08-03 : changed cdp info: short interface name, dropped neighbor domain name, added S/N and Model to longoutput
2018-09-14 : fixed issue with missing AP, fixed issue with SSH check