Remove the hardware page

It described Georgia Tech machines (Instinct, CRNCH Rogues Gallery,
PACE Phoenix, ICE) that no longer apply. Its navbar entry was already
commented out, so nothing linked to it; that dead entry goes too.

Author: sbryngelson

_config.yml

@@ -39,7 +39,6 @@ nav_pages:
   - name: teaching
   - name: software
     display: MFC
-  # - name: hardware
 
 include:
   - .htaccess