[zsh] Use neovim as vim if available

zshrc

@@ -26,7 +26,13 @@ if [ -d "$HOME/emsdk" ]; then
     PATH="$PATH:~/emsdk:~/emsdk/node/12.9.1_64bit/bin:~/emsdk/fastcomp/emscripten" #:~/emsdk/fastcomp/emscripten/tools"
 fi
 export BROWSER='/usr/bin/w3m -T "text/html"'
-export EDITOR=/usr/bin/vim
+if which nvim > /dev/null 2>&1; then
+  export EDITOR=/usr/bin/nvim
+else
+  export EDITOR=/usr/bin/vim
+fi
+# Disable `less` history file
+export LESSHISTFILE='/dev/null'
 export GPG_TTY="$(tty)"
 # Prevent mime associations by wine
 export WINEPREFIX="$HOME/.wine"