add more doc to cog_cython.py
add more doc to cog_cython.py

hughperkins/DeepCL,FighterLYL/DeepCL,pimms/DeepCL,mrgloom/DeepCL,Peilong/DeepCL,hughperkins/DeepCL,MiniLight/DeepCL,mrgloom/DeepCL,FighterLYL/DeepCL,Peilong/DeepCL,MiniLight/DeepCL,hughperkins/DeepCL,FighterLYL/DeepCL,MiniLight/DeepCL,hughperkins/DeepCL,pimms/DeepCL,FighterLYL/DeepCL,Peilong/DeepCL,MiniLight/DeepCL,MiniLight/DeepCL,mrgloom/DeepCL,mrgloom/DeepCL,pimms/DeepCL,pimms/DeepCL,mrgloom/DeepCL,FighterLYL/DeepCL,Peilong/DeepCL,Peilong/DeepCL,pimms/DeepCL,hughperkins/DeepCL