Update to fix packages without any archive version which are still referenced in the archives file

DESCRIPTION

@@ -1,7 +1,7 @@
 Package: Rpacman
 Type: Package
 Title: Very simple package manager for R
-Version: 1.0.12
+Version: 1.0.13
 Date: 2022-05-31
 Authors@R: person("Craig", "Williams", email = "craig@avsdev.uk", role = c("aut", "cre"))
 URL: https://avsdev.uk/R/Rpacman

R/fetch_available_archives.R

@@ -11,6 +11,9 @@
     packageVersions <- gsub("^([^/]+)/[^_]+_(.+).tar.gz", "\\1%%\\2", rownames(pkg))
     packageVersions <- strsplit(packageVersions, "%%")
     packageVersions <- do.call(rbind, packageVersions)
+    if (is.null(packageVersions)) {
+      return(NULL)
+    }
     pkg[,c("package","version")] <- packageVersions
     sortOrder <- sort(pkg$version, index.return = TRUE)$ix
     pkg[sortOrder,c("package", "version")]