Merge #83: Clock: Time Extent, Maker, and Associated Traits

e785a7f time extent: overhaul tests naming scheme (Cameron Garnham)
3d743ed time extent: use snake_case for module name (Cameron Garnham)
8653f9a time extent: rename `TimeExtentMaker` for clarity (Cameron Garnham)
0cab30c time extent: add tests and some corrections (Cameron Garnham)
028644d clock: time extent, maker, and associated traits (Cameron Garnham)

Pull request description:

  `TimeExtent` is a simple structure that contains base increment (duration), and amount (a multiplier for the base the base increment). The resulting product of the base and the multiplier is the total duration of the time extent.

  `TimeExtentClock` is a helper that generates time extents based upon the increment length and the time of the clock, this clock is specialised according to the `test` predicate with the `DefaultClockExtentMaker` type.

  These modules will be used by the later connection cookie implementation.

ACKs for top commit:
  da2ce7:
    ACK e785a7f

Tree-SHA512: ba667cb47f9c5116355cbf34ea275d46404b09c5c1ff4aa825db2da49884a430174849b22c22a1b32b206bf06d7c34a054dc76b94a24e267205df909d0b3045d

src/protocol/clock.rs → src/protocol/clock/mod.rs

@@ -1,5 +1,5 @@
 use std::num::IntErrorKind;
-pub use std::time::Duration;
+use std::time::Duration;
 
 pub type DurationSinceUnixEpoch = Duration;
 
@@ -240,9 +240,11 @@ mod stopped_clock {
 
             #[test]
             fn it_should_get_app_start_time() {
-                const TIME_AT_WRITING_THIS_TEST: Duration = Duration::new(1662983731, 000022312);
+                const TIME_AT_WRITING_THIS_TEST: Duration = Duration::new(1662983731, 22312);
                 assert!(get_app_start_time() > TIME_AT_WRITING_THIS_TEST);
             }
         }
     }
 }
+
+pub mod time_extent;