MAINT: Mark .ipynb files as binary.
MAINT: Mark .ipynb files as binary.

Makes `git grep` not print the binary content of png files.

Scapogo/zipline,florentchandelier/zipline,bartosh/zipline,bartosh/zipline,Scapogo/zipline,alphaBenj/zipline,enigmampc/catalyst,humdings/zipline,florentchandelier/zipline,humdings/zipline,enigmampc/catalyst,alphaBenj/zipline,quantopian/zipline,quantopian/zipline