add filters for outage rest interface

On the outages page, one can filter the displayed list based on:

outtype: current, resolved, both
intf: <ipaddress>
service: <string>
lostafter: <datetime>
lostbefore: <datetime>

The rest interface for outages though doesn't have a parser for these particular entries so you need to know the backend queries to get the same results.

For example, to get all current outages, your rest query would need to have (with white spaces encoded), and

converted to a date:

query=ifregainedservice is null or ifregainedservice >

It would be nice to be able to use the same parameters as you could on the other page.