[O] Remove notes blocks from latex export

[Joon Ro]

Hi,
org-reveal uses notes blocks (#+BEGIN_NOTES) for speaker notes, and I want to 
remove those blocks when I export those slides to latex for handouts.For src 
blocks it can be done easily with org-export-filter-src-block-functions - is 
there any way to do this with generic blocks? 
Thank you and happy new year!Joon