chore(zsh/docker): Upgrade alias to 0.9
feat(zsh/aliases): Init topmem
feat(zsh/git): Add alias gcheckpoint
feat(zsh/ssh-agent): Don't run inside a container

Use $HOSTNAME as the hint (until something more reliable comes up).
fix(zsh/core): Error if .zsh_history does not yet exist
fix(zsh/ruby): Add GEM_PATH
feat(zsh/bin/node/npm-latest): Init