Url update.

.Rbuildignore

@@ -16,3 +16,4 @@
 ^docs$
 ^.*\.Rproj$
 ^\.Rproj\.user$
+^CRAN-SUBMISSION$

DESCRIPTION

@@ -1,6 +1,6 @@
 Package: listdown
 Title: Create R Markdown from Lists
-Version: 0.5.1
+Version: 0.5.2
 Authors@R: c(
   person("Michael J.", "Kane",
     role = c("aut", "cph", "cre"),

vignettes/listdown.rmd

@@ -110,7 +110,7 @@ doc <- c(
 cat("\n", paste(doc, collapse = "\n"))
 ```
 
-The `listdown()` function provides *document-wide* R chunk options for displaying computational components. The chunk options are exactly the same as those in the R markdown document and can be used to tailor the default presentation for a variety of needs. The complete set of options can be found in the [R Markdown Reference Guide](https://rstudio.com/wp-content/uploads/2015/03/rmarkdown-reference.pdf). As a concrete example, the code used to create present the plots could be hidden in the output document using the following code.
+The `listdown()` function provides *document-wide* R chunk options for displaying computational components. The chunk options are exactly the same as those in the R markdown document and can be used to tailor the default presentation for a variety of needs. The complete set of options can be found in the [R Markdown Reference Guide](https://www.rstudio.com/wp-content/uploads/2015/03/rmarkdown-reference.pdf). As a concrete example, the code used to create present the plots could be hidden in the output document using the following code.
 
 ```{r}
 ld <- listdown(load_cc_expr = readRDS("comp-comp.rds"),