[SPARK-16822] [DOC] [Support latex in scaladoc with MathJax]

[jagadeesanas2]

What changes were proposed in this pull request?

LaTeX is rendered as simple code, in LinearRegression.scala

{{{
 L = 1/2n||\sum_i w_i(x_i - \bar{x_i}) / \hat{x_i} - (y - \bar{y}) / \hat{y}||^2 + regTerms
}}}

[jagadeesanas2]

cc @lins05 @srowen

[SparkQA]

Test build #64044 has finished for PR 14711 at commit 7cacb11.

• This patch passes all tests.
• This patch merges cleanly.
• This patch adds no public classes.

[srowen]

I'm confused, isn't this related to SPARK-17095? you're already fixing mathjax issues there.

[jagadeesanas2]

@srowen , Actually this fix (mathjax issues) for this JIRA only. As @sethah mentioned in his comment, he is working on SPARK-17095, he will send PR soon.

[srowen]

I'm referring to your PR #14688 I don't see that he said he's working on it, just that he encountered it while working on something else. I'd rather fix the mathjax issues of both forms in that PR at once.

[jagadeesanas2]

ohh i got it. Can i close this PR..?

[srowen]

You can just merge the work over to the other PR. I think we want to fix latex that's rendering as code accidentally, and latex whose closing braces are mangled by scaladoc.