add a redirect document for old index_toc page

mmcky · mmcky · commit 8ade716e0b6e · 2020-10-27T11:21:37.000+11:00
diff --git a/lectures/index_toc.md b/lectures/index_toc.md
@@ -0,0 +1,3 @@
+```{only} html
+<meta http-equiv="Refresh" content="0; url=intro.html" />
+```

Original file line number	Diff line number	Diff line change
`@@ -0,0 +1,3 @@`
	`1`	+```{only} html
	`2`	`+<meta http-equiv="Refresh" content="0; url=intro.html" />`
	`3`	+```