nodes: rename Render* to Draw*

[mbouron]

RenderToTexture is not renamed as it is not a drawing node.

[ubitux]

Doc needs some more adjustments:

doc/usr/expl/media-time-remapping.md:sub-tree (in our case, it will typically be a [Render] using a [Media] node as
doc/usr/expl/media-time-remapping.md:[Render]: /usr/ref/libnopegl.md#render
doc/usr/expl/noise.md:attached to the associated [Render] or [Compute].
doc/usr/expl/noise.md:[Render]: /usr/ref/libnopegl.md#render
doc/usr/expl/scopes.md:can be attached to [Render] vertex or fragment resources, or [Compute]
doc/usr/expl/scopes.md:[Render]: /usr/ref/libnopegl.md#render
doc/usr/expl/shaders.md:When constructing a graphic pipeline (`Render` node), the geometry information
doc/usr/expl/shaders.md:`Render.attributes` or `Render.instance_attributes`. These attributes will be
doc/usr/expl/shaders.md:`Render.vert_resources`. Since this parameter is a dictionary, the user can
doc/usr/expl/shaders.md:`Render.frag_resources`. Since this parameter is a dictionary, the user can
doc/usr/expl/shaders.md:`Render.vert_resources`, `Render.frag_resources` or `Compute.resources` to be
doc/usr/expl/shaders.md:render = Render(geometry, program)
doc/usr/howto/c-api.md:and how a basic `Render` node works. If not, you are encouraged to check out
doc/usr/howto/path.md:Rendering a path with a single cubic curve looks like this:
doc/usr/howto/shapes.md:Rendering a triangle
doc/usr/howto/shapes.md:Rendering a quadrilateral
doc/usr/howto/shapes.md:Rendering a circle with 64 points
doc/usr/howto/shapes.md:Rendering a custom geometry composed of 4 random points
doc/usr/ref/pynopegl.md:`*Dict`                 | `dict`                              | `render = Render(geometry, frag_resources={'tex0': t0, 'tex1': t1})`

[ubitux]

You might also want to git ls-files|xargs sed -i 's/render =/draw =/'

Edit: and a 2nd pass with git ls-files|xargs sed -i 's/render\(\s\+=\)/draw \1/'

Edit2: yes I'm an idiot, you need to rename the usage after that as well...

[ubitux]

Please update the next branch in the nope.demos repository after pushing

[ubitux]

Most pynopegl-utils/pynopegl_utils/examples scenes are broken and need adjustments

[ubitux]

LGTM, see my comment on the nope.demos repository though