feat(tldr): add tldr plugin (#12429)

plugins/tldr/tldr.plugin.zsh

@@ -0,0 +1,19 @@
+tldr-command-line() {
+    # if there is no command typed, use the last command
+    [[ -z "$BUFFER" ]] && zle up-history
+
+    # if typed command begins with tldr, do nothing
+    [[ "$BUFFER" = tldr\ * ]] && return
+
+    # get command and possible subcommand
+    # http://zsh.sourceforge.net/Doc/Release/Expansion.html#Parameter-Expansion-Flags
+    local -a args
+    args=(${${(Az)BUFFER}[1]} ${${(Az)BUFFER}[2]})
+
+    BUFFER="tldr ${args[1]}"
+}
+
+zle -N tldr-command-line
+# Defined shortcut keys: [Esc]tldr
+bindkey "\e"tldr tldr-command-line
+