use bibentry() instead of citEntry() per instruction of R CMD check o…

…n CRAN

inst/CITATION

@@ -1,31 +1,24 @@
-citHeader("To cite the 'tinytex' package in publications use:")
-
 year = sub('.*(2[[:digit:]]{3})-.*', '\\1', meta$Date, perl = TRUE)
 vers = paste('R package version', meta$Version)
+if (length(year) == 0) year = format(Sys.Date(), '%Y')
 
-citEntry(
-  entry = 'manual',
+bibentry(
+  'manual',
   title = paste('tinytex:', meta$Title),
   author = Filter(function(p) 'aut' %in% p$role, as.person(meta$Author)),
   year = year,
   note = vers,
-  url = meta$URL,
-  textVersion = paste('Yihui Xie (', year, '). tinytex: ', meta$Title, '. ', vers, '.', sep = '')
+  url = meta$URL
 )
 
-citEntry(
-  entry = 'article',
+bibentry(
+  'article',
   title = 'TinyTeX: A lightweight, cross-platform, and easy-to-maintain LaTeX distribution based on TeX Live',
   author = 'Yihui Xie',
   journal = 'TUGboat',
   year = '2019',
   volume = '40',
   number = '1',
   pages = '30--32',
-  url = 'https://tug.org/TUGboat/Contents/contents40-1.html',
-  textVersion = paste(
-    'Yihui Xie (2019)',
-    'TinyTeX: A lightweight, cross-platform, and easy-to-maintain LaTeX distribution based on TeX Live.',
-    'TUGboat 40 (1): 30--32. https://tug.org/TUGboat/Contents/contents40-1.html'
-  )
+  url = 'https://tug.org/TUGboat/Contents/contents40-1.html'
 )