typo in faq/upgrade49.html

[Kent Watsen]

s/which we have not been dealt with so far/which have not been dealt 
with so far/

BTW, the "Final steps" section would be clearer if the text between the 
title "Final Steps" and section "1a" were put into a section called "1. 
Merging locally changed files", which then has the two existing 
subsections '1a' and '1b'.