DocC documentation support (#4)

This PR contains the work done to:
* Documented all the `private`, `internal`, and `public` interfaces on the existing codebase;
* Set the DocC documentation catalog in the project;
* Written the main `Library` article for the DocC documentation catalog;
* Added the documentation tasks in the `Makefile` file.

Reviewed-on: #4
Co-authored-by: Javier Cicchelli <javier@rock-n-code.com>
Co-committed-by: Javier Cicchelli <javier@rock-n-code.com>

Tests/Public/Services/AmiiboServiceLiveTests.swift

@@ -23,10 +23,8 @@ struct AmiiboServiceLiveTests {
     
     // MARK: Initialisers
     
-    init() throws {
-        let client = try AmiiboLiveClient()
-        
-        self.service = .init(client)
+    init() {
+        self.service = .init(.live())
     }
     
     // MARK: Functions tests