Enhance converter docstring and signature

[maximlt]

Comparing the keyword documented in the signature and defined in the docstring of the HoloViewsConverter class:

• Keywords in the signature but not in the docstring:

backlog
by
col
data
debug
fields
framewise
group_label
groupby
kind
kwds
label
persist
precompute
row
stacked
stream
subplots
use_dask
use_index
value_label
x
y

• Keywords in the docstring but not in the signature:

bgcolor
clabel
fontscale
fontsize
frame_height
frame_width
logz
max_height
max_width
min_height
min_width
padding
responsive
shared_axes
width
xaxis
xformatter
xlabel
xticks
yaxis
yformatter
ylabel
yticks

• Document undocumented keywords
• Add to the signature (might be not possible for all) keywords only documented in the docstring