runtime(r): Update R runtime files and docs (#13757)

* Update R runtime files
- Fix indentation issue with ggplot().
- Setlocal autoindent in indent/r.vim.
- New syntax option: rmd_include_latex.
- Clear syn iskeyword to recognize _ as keyword.
- Document some options.
- remove the test has("patch-7.4.1142")
- Update changed date of doc files

Signed-off-by: Jakson Alves de Aquino <jalvesaq@gmail.com>
Signed-off-by: Christian Brabandt <cb@256bit.org

runtime/doc/filetype.txt

@@ -1,4 +1,4 @@
-*filetype.txt*  For Vim version 9.0.  Last change: 2023 Dec 05
+*filetype.txt*  For Vim version 9.0.  Last change: 2023 Dec 23
 
 
 		  VIM REFERENCE MANUAL    by Bram Moolenaar
@@ -779,6 +779,14 @@ To enable this behavior, set the following variable in your vimrc: >
 	let g:rst_style = 1
 
 
+RNOWEB							      *ft-rnoweb-plugin*
+
+The 'formatexpr' option is set dynamically with different values for R code
+and for LaTeX code. If you prefer that 'formatexpr' is not set, add to your
+|vimrc|: >
+	let rnw_dynamic_comments = 0
+
+
 RPM SPEC						*ft-spec-plugin*
 
 Since the text for this plugin is rather long it has been put in a separate