Update changelog.md
Update changelog.md

* massive catchup on versions and details
* misc formatting fixes
* added header
* added semver info
angeemaree/nerd-fonts,hoop33/nerd-fonts,cheba/nerd-fonts,PatrickCoffey/nerd-fonts,CestDiego/nerd-fonts,CestDiego/nerd-fonts,cheba/nerd-fonts,ryanoasis/font-nerd-icons,angeemaree/nerd-fonts,PatrickCoffey/nerd-fonts,hoop33/nerd-fonts,ryanoasis/font-nerd-icons