Re-add list_url for all R packages (#6110)

* r-igraph: find old packages in the archive

Fixes #6104.

* r-irlba: find old packages in the archive

Fixes #6101.

* r-lazyeval: find old packages in the archive

Fixes #6102.

* packages: set list_url for all packages hosted on CRAN

* packages: consistently use the CRAN archive URLs

var/spack/repos/builtin/packages/r-highr/package.py

@@ -33,5 +33,6 @@ class RHighr(RPackage):
 
     homepage = "https://github.com/yihui/highr"
     url      = "https://cran.r-project.org/src/contrib/highr_0.6.tar.gz"
+    list_url = "https://cran.r-project.org/src/contrib/Archive/highr"
 
     version('0.6', 'bf47388c5f57dc61962362fb7e1d8b16')