Update the plugins managment. Add the function 'omz-plugin' (inspired from bash-it)

plugins/available/mix-fast/mix-fast.plugin.zsh

@@ -0,0 +1,29 @@
+_mix_refresh () {
+  if [ -f .mix_tasks ]; then
+    rm .mix_tasks
+  fi
+  echo "Generating .mix_tasks..." > /dev/stderr
+  _mix_generate
+  cat .mix_tasks
+}
+
+_mix_does_task_list_need_generating () {
+  [ ! -f .mix_tasks ];
+}
+
+_mix_generate () {
+  mix --help | grep -v 'iex -S' | tail -n +2 | cut -d " " -f 2 > .mix_tasks
+}
+
+_mix () {
+  if [ -f mix.exs ]; then
+    if _mix_does_task_list_need_generating; then
+      echo "\nGenerating .mix_tasks..." > /dev/stderr
+      _mix_generate
+    fi
+    compadd `cat .mix_tasks`
+  fi
+}
+
+compdef _mix mix
+alias mix_refresh='_mix_refresh'