Add route files, show overview

CHDataManagement/Workouts/Time+String.swift

@@ -0,0 +1,19 @@
+import Foundation
+
+extension TimeInterval {
+
+    var timeString: String {
+        let seconds = Int(rounded())
+        guard seconds > 59 else {
+            return "\(seconds) s"
+        }
+        let min = seconds / 60
+        let secs = seconds % 60
+        guard min > 59 else {
+            return String(format: "%02d:%02d", min, secs)
+        }
+        let hours = min / 60
+        let mins = min % 60
+        return String(format: "%d:%02d:%02d", hours, mins, secs)
+    }
+}