Add paths to configuration

WebsiteGenerator/Files/Configuration.swift

@@ -5,4 +5,16 @@ struct Configuration {
     let pageImageWidth: Int
 
     let minifyCSSandJS: Bool
+
+    let contentPath: String
+
+    let outputPath: String
+
+    var contentDirectory: URL {
+        .init(fileURLWithPath: contentPath)
+    }
+
+    var outputDirectory: URL {
+        .init(fileURLWithPath: outputPath)
+    }
 }