Remove redundant hostaddress

[akomakom]

• Removes hostaddress when hostaddress == hostalias
• Makes host/service output optional (and output more concise if these are not supplied, previously would output None)

If you want, I can add the _with_alias and _without_alias block for host template also for symmetry (I'm not clear on why only service template had both hostalias and hostaddress)