Release 6.22.2: Added properties to pop3.properties to control ping operation for POP3 accounts

[Guest]

# Whether ping operation is allowed for POP3 account
# Many POP3 account limit number of allowed login attempts in a certain time interval
# Default is false
com.openexchange.pop3.allowPing=false

# Whether denied ping operation shall be indicated as a warning to client
# Only effective if com.openexchange.pop3.allowPing is set to false.
# Default is true
com.openexchange.pop3.logDeniedPing=true