fake data: align gsp_id with x and y coords

[peterdudfield]

Detailed Description

Make sure x and y center from metadata are aligned with GSP id

Context

Useful for fake data to represent real data

Possible Implementation

Options

1. Create gsp id when creating metadata
2. when picking random gsp ids, search for the closest gsp id to the center
3. Create x and y centers of gsp locations in metadata, then when creating gsp id search using the x and y centers