Contribute: Adding documentation to new class at 3.0

Hi! I'm trying to contribute with a new class to the OpenCV 3 but I'm stuck with the documentation. How can I add it? I can't find the .rst files (at 2.4 repo they were at opencv/modules//doc). Should I add my project (with cpp, hpp and rst files) to the 2.4 instead of 3.0? Maybe I'm just being dumb, but I getting tired of trying to find how I should add the rst files. Thanks in advance!