Search term on load may bomb mermaid chart

[McShelby]

Having a search term of "Alice" active on load of the page in the mermaid-exampleSite will "bomb" the mermaid chart.

This is because the mermaid chart and the execution of text highlightning are executed from different onLoad handlers.

Assuming that #410 will be merged before, this can be fixed by merging both onLoad handlers together.

One is contained in learn.js, the other in `hugo-learn.js'. I don't understand this separation anyway and it wasn't clear from the git history. Because of that, I would prefer both files into one.

[McShelby]

Is fixed in the fork