Re-arrange the HoloViews Converter docstrings into more meaningful groups.

[Azaya89]

"""
I think that's for another PR but you can already start thinking about better group the options:

• there's a _data_options but not Data Options section in the docstring
• maybe one category specifically for streaming options
• it'd be nice to have col and row grouped in the same option and be close with each other

"""

Originally posted by @maximlt in #1511 (review)

[maximlt]

Probably a good idea to work in this issue while addressing #1506. The main goal will be to group the options in categories that make sense and that are not too broad to avoid having too many options, since in the end we'll have a reference page per options group. At least that's the goal for now.

[Azaya89]

i agree. That makes sense. One PR kill two Issues :)