[PDB-tech] new query / client features

[Matt Griswold]

We're going back and trying to address a lot of the ease of use
complaints now, starting with improved querying which will allow for
easier retrieval of related entities. So far we have:

  * /fac?net_id=X - list facilities where network is present
  * /fac?ix_id=X - list facilities where exchange is present

  * /ix?net_id=X - list exchanges where network is present
  * /ix?fac_id=X - list exchanges at facility

  * /net?fac_id=X - list networks at facility
  * /net?ix_id=X - list networks at exchange
  * /net?ixlan_id=X - list networks at ixlan

  * /netixlan?ix_id=X - list netixlan objects for exchange

  * /ixpfx?ix=X - list all prefixes at exchange

All of these queries support our query filters on related object
fields, for example:

  * /ix?net__asn=XXX - list all exchanges where network with matching
ASN is present
  * /net?ix__name__startswith=XXX - list all networks at exchanges
where exchange name starts with XXX

Anyone else have suggestions on which end points to add?

The peeringdb-py client needs refactoring and a fair amount of work, in
fact, I didn't mean to have it still in this state by release, so my
apologies. Will be refactoring out the library to be fairly standalone,
adding functions to include the above queries automatically. Also will
be adding a whois feature to replace the old whois displays yet allow
for auth so it can also display contacts.

Changes will be showing up at https://github.com/peeringdb/peeringdb-py
as soon as they're complete.

Again, any other suggestions / improvements are welcome, now is the
time to bring them up.

Thanks!