Calculate the bounding box with a point and radius

[nimashariatian]

hi guys,
first of all, thank you so much for this library!
its amazing !

i just wanted to make a suggestion, it would be great if we could
calculate the bounding box coordinates of a given point at its center along with a radius.

use case:
assuming, having bunch of points saved in the database (longitudes an latitudes),
this could help us find records that are within X miles / kms of a given point.

here is an example of ruby implementation:
https://github.com/alexreisner/geocoder/blob/master/lib/geocoder/calculations.rb#L212

again,
thanks for all the hard work :)

[yltsrc]

PRs are welcome :)
in other way I can do it, but I can't say when...

[nimashariatian]

perfect, ill fork and work on it i guess.. i am actually kind of hoping to eventually do a pour of the entire https://github.com/alexreisner/geocoder
from ruby -> elixir