README.md code example does not compile

[andrew-barnard]

Preamble
error[E0412]: cannot find type Utm in this scope
--> src\main.rs:8:30
|
8 | let utm: Utm = coord.clone().into();
| ^^^ not found in this scope

perhaps change line 8 to:
let utm: utm::Utm = coord.clone().into();