add note for china users

index.html

@@ -29,11 +29,26 @@
   _email="--$(echo "$_email" | tr '=' ' ')"
 fi
 
+
+_url="https://raw.githubusercontent.com/acmesh-official/acme.sh/$BRANCH/acme.sh"
+
+
+_get=""
+
 if _exists curl && [ "${ACME_USE_WGET:-0}" = "0" ]; then
-  curl https://raw.githubusercontent.com/acmesh-official/acme.sh/$BRANCH/acme.sh | sh -s -- --install-online $_email "$@"
+  _get="curl -L"
 elif _exists wget ; then
-  wget -O -  https://raw.githubusercontent.com/acmesh-official/acme.sh/$BRANCH/acme.sh | sh -s -- --install-online $_email "$@"
+  _get="wget -O -"
 else
   echo "Sorry, you must have curl or wget installed first."
   echo "Please install either of them and try again."
+  exit 1
 fi
+
+
+if ! $_get "$_url" | sh -s -- --install-online $_email "$@"; then
+  echo "Install error"
+  echo "中国大陆用户请参考:"
+  echo "https://github.com/acmesh-official/acme.sh/wiki/Install-in-China"
+fi
+