Struct for PostgreSQL line.
line
Note, lines are stored in PostgreSQL in the form {a, b, c}, which parameterizes a line as a*x + b*y + c = 0.
{a, b, c}
a*x + b*y + c = 0
a
b
c
@type t() :: %Postgrex.Line{a: float(), b: float(), c: float()}