Rename StopWatch to Stopwatch. Add new Stopwatch.start() and Stopwatch.reset().

tests/co19/co19-frog.status

Index: tests/co19/co19-frog.status
diff --git a/tests/co19/co19-frog.status b/tests/co19/co19-frog.status
index b8e5870ebae1794d329cb67f3ad3594cd47f1c7c..f66d98f26a25fe3ccffaf13b8fa3fda6c56d8088 100644
--- a/tests/co19/co19-frog.status
+++ b/tests/co19/co19-frog.status
@@ -217,7 +217,6 @@ LibTest/core/Proxy/Proxy.forPort/Proxy/Proxy.forPort/A01/t01: Fail
 LibTest/core/Proxy/call/Proxy/call/A01/t01: Fail
 LibTest/core/Duration/Duration/Duration/A03/t01: Fail
 LibTest/core/Map/putIfAbsent/Map/putIfAbsent/A01/t09: Fail
-LibTest/core/StopWatch/start/StopWatch/start/A01/t02: Fail
 LibTest/core/double/operatorLT/double/operatorLT/A01/t03: Fail
 LibTest/core/double/A01/t01: Fail
 LibTest/core/double/operatorLT/double/operatorLT/A02/t01: Fail
@@ -577,3 +576,14 @@ LibTest/core/List/some/List/some/A01/t02: Fail
 LibTest/core/List/every/List/every/A01/t02: Fail
 LangGuideTest/02_Language_Constructs/02_6_Functions/A04/t01: Fail
 LangGuideTest/02_Language_Constructs/02_2_Interface/A01/t01: Fail
+
+# The following tests fail due to renaming of StopWatch to Stopwatch.
+[ $component == frog || $component == frogsh || $component == leg ]
+LibTest/core/StopWatch/StopWatch/StopWatch/A01/t01: Fail
+LibTest/core/StopWatch/start/StopWatch/start/A01/t01: Fail
+LibTest/core/StopWatch/start/StopWatch/start/A01/t02: Fail  # Also broken test.
+LibTest/core/StopWatch/start/StopWatch/start/A01/t03: Fail
+LibTest/core/StopWatch/elapsed/StopWatch/elapsed/A01/t01: Fail
+LibTest/core/StopWatch/elapsed/StopWatch/elapsed/A01/t02: Fail
+LibTest/core/StopWatch/elapsed/StopWatch/elapsed/A01/t03: Fail
+LibTest/core/StopWatch/frequency/StopWatch/frequency/A01/t01: Fail