Fixes mon_addresses when using linux-ha ip aliases

linux-ha has an IPaddr and IPaddr2 resource to create HA IP aliases
However, it assigns a broadcast address to this IP
This changes changes mon_addresses to ignore IP addresses that have a different
netmask along with the previous check for the existance of broadcast
Merge pull request #126 from hufman/fix-ipaliases

Fixes mon_addresses when using linux-ha ip aliases