Adjust HTML table style (GH2209)

[jorisvandenbossche]

Closes #2209

@ellisonbg I now set line-height, white-space and max-width to new values. But I think, I could also remove those lines since they are the default values anyway.

[jorisvandenbossche]

Regarding line-height / padding.

Current master:

With this PR, it set line-height from 1.0 to 'normal', because otherwise multi-line cells looked weird (see the issue), but that also causes a normal table without wrapped cells look much more spacious (on my laptop: text is 20px height with 2x 6px padding -> 32 px):

If I adjust padding from 0.5 to 0.3, it becomes more similar to master (same text height of 20px but with 2x 3.6px padding -> 27.2 px):

On master it has a text line height of 12 px, with padding of 2x 6px, giving 24px in total.

[ellisonbg]

Thanks! Merging...

[jorisvandenbossche]

@ellisonbg Thanks for merging!

I personally like the one above with a bit less padding (third figure) to have it more similar with master before this PR (first picture), but that is more a matter of personal taste, so leave that decision up to you :-)
(and I think such small adjustments can always be made after in a next small release after using it a bit more in practice?)

[takluyver]

Yep, I think it's totally fine to make adjustments in 5.1