install/windows: add install/win as an alias, just for good measure

Currently when clicking on the `Install` link on the front page on
Windows, it redirects to the (non-existing) `/install/win` page. Let's
follow Postel's Law and redirect that to the correct location.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>

Author: dscho

content/install/windows.html

@@ -4,6 +4,7 @@
 aliases:
 - /download/win
 - /downloads/win
+- /install/win
 ---
 
 <div id="main">