Move file archive to end of stuff list

input/blog/2016/2016_05_25_spacenav_plus.md

 flattr: true
 github: https://github.com/xythobuz/spacenav-plus
 parent: stuff
-position: 100
+position: 90
 ---
 
 ## {{ page["post"] }}

input/stuff/archive.md

 title: File Archive
 parent: stuff
-position: 90
+position: 1000
 ---
 
 ### {{ page.title }}