Add tool that generates an html file comparing emoji images.
Add tool that generates an html file comparing emoji images.

This uses nototools to get unicode names.  It relies on new
api in nototools.unicode_data to get data/names of proposed emoji
that are not currently approved and so not in the standard data
files.

mxalbert1996/emojione-android,dougfelt/noto-emoji,googlei18n/noto-emoji,googlei18n/noto-emoji,googlefonts/noto-emoji,moyogo/noto-emoji,googlei18n/noto-emoji,googlefonts/noto-emoji,moyogo/noto-emoji,dougfelt/noto-emoji,julroy67/noto-emoji,radiocane/noto-emoji,googlefonts/noto-emoji,radiocane/noto-emoji,julroy67/noto-emoji,dougfelt/noto-emoji