Add Buffer Time Travel as a vim til.

vim/buffer-time-travel.md

@@ -0,0 +1,20 @@
+# Buffer Time Travel
+
+Vim allows you to go to an *earlier* text state for a buffer with
+`:earlier`. For instance, if you want to see the state of the buffer from 10
+minutes ago:
+
+```
+:earlier 10m
+```
+
+Similarly, you can move back toward the present text state of the buffer
+with `:later`. If 10 minutes earlier was too far, you can come back 5
+minutes like so:
+
+```
+:later 5m
+```
+
+I encountered these in [Nick Nisi's 'Vim +
+Tmux'](https://www.youtube.com/watch?v=5r6yzFEXajQ) talk.