Add date to release notes.
Add date to release notes.

ChristopherHogan/cython,da-woods/cython,fabianrost84/cython,scoder/cython,c-blake/cython,c-blake/cython,ChristopherHogan/cython,c-blake/cython,da-woods/cython,cython/cython,cython/cython,cython/cython,da-woods/cython,scoder/cython,scoder/cython,fabianrost84/cython,c-blake/cython,scoder/cython,ChristopherHogan/cython,c-blake/cython,da-woods/cython,fabianrost84/cython,cython/cython,fabianrost84/cython,fabianrost84/cython