rate.sleep timings

$ ./build/rclcpp/test_rate 
Running main() from gtest_main.cc
[==========] Running 2 tests from 1 test case.
[----------] Global test environment set-up.
[----------] 2 tests from TestRate
[ RUN      ] TestRate.rate_basics
DELTA WAS:99989974
[       OK ] TestRate.rate_basics (500 ms)
[ RUN      ] TestRate.wall_rate_basics
DELTA WAS:99995146
[       OK ] TestRate.wall_rate_basics (501 ms)
[----------] 2 tests from TestRate (1001 ms total)

[----------] Global test environment tear-down
[==========] 2 tests from 1 test case ran. (1001 ms total)
[  PASSED  ] 2 tests.
tfoote@yeti:~/work/ros2/tf3 Last: [0] (1s Seconds)
$ ./build/rclcpp/test_rate 
Running main() from gtest_main.cc
[==========] Running 2 tests from 1 test case.
[----------] Global test environment set-up.
[----------] 2 tests from TestRate
[ RUN      ] TestRate.rate_basics
DELTA WAS:99987988
[       OK ] TestRate.rate_basics (500 ms)
[ RUN      ] TestRate.wall_rate_basics
DELTA WAS:99998964
[       OK ] TestRate.wall_rate_basics (501 ms)
[----------] 2 tests from TestRate (1001 ms total)

[----------] Global test environment tear-down
[==========] 2 tests from 1 test case ran. (1001 ms total)
[  PASSED  ] 2 tests.
tfoote@yeti:~/work/ros2/tf3 Last: [0] (1s Seconds)
$ ./build/rclcpp/test_rate 
Running main() from gtest_main.cc
[==========] Running 2 tests from 1 test case.
[----------] Global test environment set-up.
[----------] 2 tests from TestRate
[ RUN      ] TestRate.rate_basics
DELTA WAS:100038758
[       OK ] TestRate.rate_basics (500 ms)
[ RUN      ] TestRate.wall_rate_basics
DELTA WAS:99996847
[       OK ] TestRate.wall_rate_basics (501 ms)
[----------] 2 tests from TestRate (1001 ms total)

[----------] Global test environment tear-down
[==========] 2 tests from 1 test case ran. (1001 ms total)
[  PASSED  ] 2 tests.
tfoote@yeti:~/work/ros2/tf3 Last: [0] (1s Seconds)
$ ./build/rclcpp/test_rate 
Running main() from gtest_main.cc
[==========] Running 2 tests from 1 test case.
[----------] Global test environment set-up.
[----------] 2 tests from TestRate
[ RUN      ] TestRate.rate_basics
DELTA WAS:99991648
[       OK ] TestRate.rate_basics (500 ms)
[ RUN      ] TestRate.wall_rate_basics
DELTA WAS:100012350
[       OK ] TestRate.wall_rate_basics (501 ms)
[----------] 2 tests from TestRate (1001 ms total)

[----------] Global test environment tear-down
[==========] 2 tests from 1 test case ran. (1001 ms total)
[  PASSED  ] 2 tests.
tfoote@yeti:~/work/ros2/tf3 Last: [0] (1s Seconds)
$ ./build/rclcpp/test_rate 
Running main() from gtest_main.cc
[==========] Running 2 tests from 1 test case.
[----------] Global test environment set-up.
[----------] 2 tests from TestRate
[ RUN      ] TestRate.rate_basics
DELTA WAS:99991727
[       OK ] TestRate.rate_basics (500 ms)
[ RUN      ] TestRate.wall_rate_basics
DELTA WAS:99999743
[       OK ] TestRate.wall_rate_basics (500 ms)
[----------] 2 tests from TestRate (1001 ms total)

[----------] Global test environment tear-down
[==========] 2 tests from 1 test case ran. (1001 ms total)
[  PASSED  ] 2 tests.
tfoote@yeti:~/work/ros2/tf3 Last: [0] (1s Seconds)
$ ./build/rclcpp/test_rate 
Running main() from gtest_main.cc
[==========] Running 2 tests from 1 test case.
[----------] Global test environment set-up.
[----------] 2 tests from TestRate
[ RUN      ] TestRate.rate_basics
DELTA WAS:99991818
[       OK ] TestRate.rate_basics (501 ms)
[ RUN      ] TestRate.wall_rate_basics
DELTA WAS:100003150
[       OK ] TestRate.wall_rate_basics (500 ms)
[----------] 2 tests from TestRate (1001 ms total)

[----------] Global test environment tear-down
[==========] 2 tests from 1 test case ran. (1001 ms total)
[  PASSED  ] 2 tests.
tfoote@yeti:~/work/ros2/tf3 Last: [0] (1s Seconds)
$ ./build/rclcpp/test_rate 
Running main() from gtest_main.cc
[==========] Running 2 tests from 1 test case.
[----------] Global test environment set-up.
[----------] 2 tests from TestRate
[ RUN      ] TestRate.rate_basics
DELTA WAS:99998649
[       OK ] TestRate.rate_basics (500 ms)
[ RUN      ] TestRate.wall_rate_basics
DELTA WAS:99999840
[       OK ] TestRate.wall_rate_basics (500 ms)
[----------] 2 tests from TestRate (1000 ms total)

[----------] Global test environment tear-down
[==========] 2 tests from 1 test case ran. (1000 ms total)
[  PASSED  ] 2 tests.
tfoote@yeti:~/work/ros2/tf3 Last: [0] (1s Seconds)
$ ./build/rclcpp/test_rate 
Running main() from gtest_main.cc
[==========] Running 2 tests from 1 test case.
[----------] Global test environment set-up.
[----------] 2 tests from TestRate
[ RUN      ] TestRate.rate_basics
DELTA WAS:99993327
[       OK ] TestRate.rate_basics (500 ms)
[ RUN      ] TestRate.wall_rate_basics
DELTA WAS:99994834
[       OK ] TestRate.wall_rate_basics (500 ms)
[----------] 2 tests from TestRate (1000 ms total)

[----------] Global test environment tear-down
[==========] 2 tests from 1 test case ran. (1000 ms total)
[  PASSED  ] 2 tests.