Revert "drop Mailpit feature (#1933)" (#1973)

This reverts commit d14da1f.

scripts/features/mailpit.sh

@@ -0,0 +1,41 @@
+#!/usr/bin/env bash
+
+if [ -f ~/.homestead-features/wsl_user_name ]; then
+    WSL_USER_NAME="$(cat ~/.homestead-features/wsl_user_name)"
+    WSL_USER_GROUP="$(cat ~/.homestead-features/wsl_user_group)"
+else
+    WSL_USER_NAME=vagrant
+    WSL_USER_GROUP=vagrant
+fi
+
+export DEBIAN_FRONTEND=noninteractive
+
+if [ -f /home/$WSL_USER_NAME/.homestead-features/mailpit ]
+then
+    echo "mailpit already installed."
+    exit 0
+fi
+
+touch /home/$WSL_USER_NAME/.homestead-features/mailpit
+chown -Rf $WSL_USER_NAME:$WSL_USER_GROUP /home/$WSL_USER_NAME/.homestead-features
+
+curl -sL https://raw.githubusercontent.com/axllent/mailpit/develop/install.sh | sh
+
+chown -f $WSL_USER_NAME:$WSL_USER_GROUP /usr/local/bin/mailpit
+
+cat > /etc/systemd/system/mailpit.service << EOF
+[Unit]
+Description=Mailpit
+After=network.target
+
+[Service]
+User=vagrant
+ExecStart=/usr/bin/env /usr/local/bin/mailpit
+
+[Install]
+WantedBy=multi-user.target
+EOF
+
+systemctl disable --now mailpit
+
+systemctl enable --now mailpit