Support for (some) colour fonts

Various colour fonts (e.g., emoji fonts) are now supported. Note, that certain

newer, more complex fonts are `not yet supported

<https://github.com/matplotlib/matplotlib/issues/31206>`__.

.. plot::

from pathlib import Path

from matplotlib.font_manager import FontProperties

zwj = '\U0000200D'

adult = '\U0001F9D1'

man = '\U0001F468'

woman = '\U0001F469'

science = '\U0001F52C'

technology = '\U0001F4BB'

skin_tones = ['', *(chr(0x1F3FB + i) for i in range(5))]

text = '\n'.join([

''.join(person + tone + zwj + occupation for tone in skin_tones)

for person in [adult, man, woman]

for occupation in [science, technology]

])

path = Path(plt.__file__).parent / 'tests/data/OpenMoji-color-glyf_colr_0-subset.ttf'

fig = plt.figure(figsize=(6.4, 4.8))

fig.text(0.5, 0.5, text,

font=FontProperties(fname=path), fontsize=48, linespacing=0.9,

horizontalalignment='center', verticalalignment='center')