FIX Gives a unique id to html visualization

[thomasjpfan]

Reference Issues/PRs

The CSS is now targeted to a specific container by ID, which helps isolated the CSS from other elements. Using an ID increases the specificity of the selector which gives the style in scikit-learn higher precedence.

What does this implement/fix? Explain your changes.

This resolves the issue here: INRIA/scikit-learn-mooc#146

CC @lesteve

[thomasjpfan]

Milestone this for 0.24.2 for now, open to have it moved to 1.0.

[glemaitre]

Happy with this change. @lesteve do you want to have a look at it

[lesteve]

This looks good to me (full disclosure: I didn't know you can have nested style inside a div).

Just to be sure, I'll double check this fixes the problem in the MOOC and merge if this is the case.

[lesteve]

I doubled-check and indeed this fixes it on the MOOC side, thanks a lot!

About including this in the 0.24.2 release this would be more convenient for the MOOC. The change seems innocuous enough but at the same time it is not a horrible bug that absolutely needs to be fixed in 0.24.2.

Since I am not involved in the day-to-day scikit-learn maintenance I am probably not the best person to decide so I'll let this one open for now ...

[lesteve]

OK I am going to merge this one!

Nobody complained and I have heard that 0.24.2 is not going to be a super quick bugfix-only release.