Store records with null coordinates in separate array

[mbilker]

This PR is a continuation on #61 to store coordinates in a separate array so something can be done with them later.

[vonbearshark]

At first I thought this might not be a good way to go about this. There's a lot of benefits to having only one marker array (we only have to filter through one), but that would get complex with all the conditionals checking if it was a pin or a non-placed marker. So this is probably the best solution. FWIW, it's not just null location pins, it's also pins that just don't fall within Oakland.

[mbilker]

Alright, thank you. I know that some of the police ones are outside of Oakland because the original case was reported in Oakland, say for stolen vehicles.

[vonbearshark]

Right, we've been talking about this in #13 and #61 , and the consensus is that we want to limit the map view to only Oakland (not even allowed to scroll to outside it), but we also want to show the pins that originate outside Oakland. So we want to identify if a pin would be placed outside the Oakland bounding box we have, then place it with the pins that don't have any location given.

[mbilker]

How about extraRecords for the variable name?

[vonbearshark]

nonPlacedRecords?

[mbilker]

That sounds good.