Add tests for issue sharkdp#622

examples/tests/human.nbt

@@ -10,11 +10,14 @@ assert_eq((60.1 seconds     -> human), "1 minute + 0.1 seconds")
 assert_eq((1 minute         -> human), "1 minute")
 assert_eq((1.25 minute      -> human), "1 minute + 15 seconds")
 assert_eq((2.5 minute       -> human), "2 minutes + 30 seconds")
+assert_eq(((2 min + 59.99999 s )-> human), "3 minutes")
 
 assert_eq((1 hour           -> human), "1 hour")
 assert_eq((1.5 hour         -> human), "1 hour + 30 minutes")
 assert_eq((2 hour           -> human), "2 hours")
 assert_eq((1 hour + 1 sec   -> human), "1 hour + 1 second")
+assert_eq((123 min          -> human), "2 hours + 3 minutes")
+assert_eq((1234 min         -> human), "20 hours + 34 minutes")
 
 assert_eq((1 day            -> human), "1 day")
 assert_eq((1.37 day         -> human), "1 day + 8 hours + 52 minutes + 48 seconds")
@@ -41,7 +44,7 @@ assert_eq((1 ms             -> human), "0.001 seconds")
 assert_eq((1 µs             -> human), "0.000001 seconds")
 assert_eq((1 ns             -> human), "1.0e-9 seconds")
 assert_eq((1234 ns          -> human), "0.000001234 seconds")
-assert_eq((1s + 1234 ns     -> human), "1 second")
+assert_eq((1 s + 1234 ns     -> human), "1 second")
 
 assert_eq((-1 second        -> human), "1 second ago")
 assert_eq((-7.89 hour       -> human), "7 hours + 53 minutes + 24 seconds ago")