Switch from discontinued csstidy to cssbeautify
.gitignore: ignore tmp and node_modules
Git: add mt=mergetool --no-prompt shortcut
Git: fix keychain support for github utilities
update-home: add bash_completion.d support
vimrc: drop global textwidth=80

It's not 1995…
Git: set core.precomposeunicode=true

Fun with files created on Windows…
Git: friendlier support for diffing CSV/TSV files
Git: format JavaScript source maps as JSON for diffs
Git: don't save mergetool backup files
Update shrink-vmdks.sh script