Fix a bug with adding range and non-range durations.

src/main/lombok/org/leumasjaffe/recipe/model/Duration.java

@@ -40,11 +40,11 @@ public class Duration {
 		
 		displayAs = rv.orElseThrow(() -> new IllegalArgumentException("Unknown time measure: " + tokens[1]));
 
+		minSeconds = (int) (Float.parseFloat(tokens[0]) * displayAs.inSeconds);
 		if (isRange) {
-			minSeconds = (int) (Float.parseFloat(tokens[0]) * displayAs.inSeconds);
 			maxSeconds = (int) (Float.parseFloat(tokens[2]) * displayAs.inSeconds);
 		} else {
-			maxSeconds = (int) (Float.parseFloat(tokens[0]) * displayAs.inSeconds);
+			maxSeconds = minSeconds;
 		}
 	}
 	
@@ -77,7 +77,7 @@ public class Duration {
 	@Override @JsonValue
 	public String toString() {
 		StringBuilder build = new StringBuilder();
-		if (minSeconds != 0) {
+		if (minSeconds != maxSeconds) {
 			build.append(convert(minSeconds, displayAs));
 			build.append(" - ");
 		}