CHANGELOG.rst 315.2.3

(CHANGELOG.rst)

I updated CHANGELOG.rst considering latest hrpsys-base-source
because I'd like to use SampleRobot scripts[1] in ``hrpsys`` ROS package example[2].

I created CHANGELOG.rst using [3] script.
I just concatenated ``hrpsys-base-source`` git log and ``hrpsys`` ros package git log, 
so the orders are not sorted by date.

(The orders within ``hrpsys-base-source`` are **sorted** and the orders within ``hrpsys`` are also **sorted**,
but the orders within all  ``hrpsys-base-source`` and ``hrpsys``  git log are **not sorted**.)



[1] https://github.com/fkanehiro/hrpsys-base/pull/252
[2] https://github.com/start-jsk/hrpsys/pull/97
[3] https://github.com/start-jsk/hrpsys/pull/96