twentyseconds fixes and enhancements

[Blake-Madden]

• Fix certain sidebar icons that would cause LaTeX compile issues
• Fix person's name to actually use the intended color
• Fix missing /fi that broke building with XeLaTeX
• Upgrade to fontawesome5 and add academicicons
• Make colors customizable via YAML header (examples included in the default template)
• Make fonts customizable when using XeLaTeX
• Add support for multiline date ranges (by embedding \\newline )
• Improve appearance of why data
• Make LaTeX less aggressive with its hyphenating

[mitchelloharawild]

Looks like you're still making changes, so I've set the PR to be a draft. Let me know when you're ready for the changes to be reviewed.

[Blake-Madden]

Sorry, I noticed a few small tweaks worth making this morning. I'll all done now. Thanks!