runtime(doc): document pandoc compiler and enable configuring arguments

closes: #14550

Signed-off-by: Konfekt <Konfekt@users.noreply.github.com>
Signed-off-by: Christian Brabandt <cb@256bit.org>

runtime/compiler/pandoc.vim

@@ -46,6 +46,7 @@ execute 'CompilerSet makeprg=pandoc\ --standalone' .
       \ '\ --metadata\ title=%:t:r:S' .
       \ '\ --metadata\ lang=' . matchstr(&spelllang, '^\a\a') .
       \ '\ --from=' . s:PandocFiletype(&filetype) .
+      \ '\ ' . escape(get(b:, 'pandoc_compiler_args', get(g:, 'pandoc_compiler_args', '')), ' ') .
       \ '\ --output\ %:r:S.$*\ %:S'
 
 CompilerSet errorformat="%f",\ line\ %l:\ %m

runtime/doc/quickfix.txt

@@ -1,4 +1,4 @@
-*quickfix.txt*  For Vim version 9.1.  Last change: 2023 Jan 18
+*quickfix.txt*  For Vim version 9.1.  Last change: 2023 Apr 15
 
 
 		  VIM REFERENCE MANUAL    by Bram Moolenaar
@@ -1321,6 +1321,15 @@ If Vim was started from the compiler, the :sh and some :!  commands will not
 work, because Vim is then running in the same process as the compiler and
 stdin (standard input) will not be interactive.
 
+PANDOC					*quickfix-pandoc* *compiler-pandoc*
+
+The Pandoc compiler plugin expects that an output file type extension is
+passed to make, say :make html or :make pdf.
+
+Additional arguments can be passed to pandoc:
+
+- either by appending them to make, say `:make html --self-contained` .
+- or setting them in `b:pandoc_compiler_args` or `g:pandoc_compiler_args`
 
 PERL					*quickfix-perl* *compiler-perl*
 

runtime/doc/tags

@@ -6528,6 +6528,7 @@ compiler-gcc	quickfix.txt	/*compiler-gcc*
 compiler-gnat	ft_ada.txt	/*compiler-gnat*
 compiler-hpada	ft_ada.txt	/*compiler-hpada*
 compiler-manx	quickfix.txt	/*compiler-manx*
+compiler-pandoc	quickfix.txt	/*compiler-pandoc*
 compiler-perl	quickfix.txt	/*compiler-perl*
 compiler-pyunit	quickfix.txt	/*compiler-pyunit*
 compiler-select	quickfix.txt	/*compiler-select*
@@ -9561,6 +9562,7 @@ quickfix-functions	usr_41.txt	/*quickfix-functions*
 quickfix-gcc	quickfix.txt	/*quickfix-gcc*
 quickfix-index	quickfix.txt	/*quickfix-index*
 quickfix-manx	quickfix.txt	/*quickfix-manx*
+quickfix-pandoc	quickfix.txt	/*quickfix-pandoc*
 quickfix-parse	quickfix.txt	/*quickfix-parse*
 quickfix-perl	quickfix.txt	/*quickfix-perl*
 quickfix-size	quickfix.txt	/*quickfix-size*