Whitespace optimizations

[alejandro5042]

Many editors will do this by default, and so let's get it all done at once so we don't see those diffs in future PRs.

Also removed multiple blank lines, and ensured there was a blank line after the YAML block.

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How this was made:

# Trim lines:
Get-ChildItem -Recurse -Filter *.md | ForEach-Object {(Get-Content $_.FullName) | ForEach-Object {$_.TrimEnd()} | Set-Content $_.FullName}

# Merge multiple blank lines:
Get-ChildItem -Recurse -Filter *.md | ForEach-Object {(Get-Content $_.FullName) | Out-String | % {$_ -replace "\r\n(\r\n)+", "`r`n`r`n"} | Set-Content $_.FullName}

[joseph-mueller]

Looks good