weekly.html: remove note about exp/template -> template move.

It actually occurred with the previous weekly snapshot.

R=golang-dev, adg
CC=golang-dev
https://golang.org/cl/4961066

doc/devel/weekly.html

@@ -53,7 +53,6 @@ Other changes:
 	added handling for URL attributes.
 	differentiate URL-valued attributes (such as href).
 	reworked escapeText to recognize attr boundaries.
-* exp/template: moved from exp to the main tree.
 * exp/wingui: made compatible with windows/amd64. (thanks Jaroslavas Počepko)
 * flag: add Parsed, restore Usage.
 * gc: add openbsd.