[Rd] Help page links to index.html are dead (PR#8196)

[kwright68@gmail.com]

Full_Name: Kevin Wright
Version: 2.2.0
OS: windows
Submission from: (NULL) (66.185.0.208)



On the help pages for R is a little circle with an up arrow that links to:

file:///C:/R/R220/doc/html/index.htmlu

This link is dead.  I suspect the link should be:

file:///C:/R/R220/doc/html/rwin.html

P.S. It should be obvious, but just in case, I have R installed at 
c:/R/R220