Add support new rpki-client JSON format?

[job]

The rpki-client JSON output format is slightly changing, an example of the new format can be found here: http://console.rpki-client.org/vrps.json

1. the asn value no longer is a string prefixed with AS, but rather just a simple integer.

2) a new expires key has been added: the value signifies when the VRP will expire in of seconds since the Epoch, UTC, given the expiration timers on current chain of CRLs & CAs applicable to a given VRP. Generally objects will be between 32 and 72 hours from their expiration, and every time rpki-client refreshes its data the expiration time is bumped forwards. Perhaps this can be used for more easy garbage collection / RPKI updating? (or just ignored if it isn't useful in irrd)

[mxsasha]

For point 1, this is already mostly supported, the only issue is that SLURM validationOutputFilters would not be correctly matched.

For point 2, maybe, we can take this into consideration in #497. Otherwise, extra data in the JSON is ignored, so it won't break anything.

[job]

Dear @mxsasha ,

It appears point 1 has become a blocker for some ISPs to upgrade their RPKI validators.

Would it be possible to resolve point 1 with a backport to 4.1.x ?

Kind regards,

Job

[job]

Now both variants are supported?

[mxsasha]

It should, yes. But will do a bit more testing.

[job]

I realize I should've made two issues, I updated the original posting :-)

[job]

I tested this PR applied to b16bd50

both formats (old and new) work correctly