Added ImageText

[radarhere]

ImageDraw.multiline_text currently takes 14 arguments, and ImageDraw.multiline_textbbox currently accepts 12 arguments.

#6201 would probably lead to that number increasing further, and there are some comments that wonder why calculating multiline text bounding box dimensions requires an ImageDraw instance.

I'm going to suggest adding a new ImageText class. I consider this to be a tidying of the API, rather than something motivated by a pressing need, so if this is accepted, maybe we don't need an immediate deprecation.

Before

from PIL import Image, ImageDraw
im = Image.new(mode, size)
d = ImageDraw.Draw(im)

d.multiline_textlength(text, font, direction, features, language, embedded_color)
d.multiline_textbbox(xy, text, font, anchor, spacing, align, direction, features, language, stroke_width, embedded_color)
d.text(xy, text, fill, font, anchor, spacing, align, direction, features, language, stroke_width, stroke_fill, embedded_color)

After

from PIL import ImageText
text = ImageText.ImageText(text, font, mode, spacing, direction, features, language)
text.embed_color()
text.stroke(stroke_width, stroke_fill)

text.get_length()
text.get_bbox(xy, anchor, align)

im = Image.new(mode, size)
d = ImageDraw.Draw(im)
d.text(xy, text, fill, anchor=anchor, align=align)

New features like #6201 would be made exclusive to the new class, something like text.wrap(width, height, scaling, limit).

If nothing else, this will separate the text handling logic from the rest of the ImageDraw code.