Update runtime files.

runtime/syntax/opam.vim

@@ -0,0 +1,38 @@
+" Vim syntax file
+" Language:    OPAM - OCaml package manager
+" Maintainer:  Markus Mottl        <markus.mottl@gmail.com>
+" URL:         https://github.com/ocaml/vim-ocaml
+" Last Change:
+"              2020 Dec 31 - Added header (Markus Mottl)
+
+if exists("b:current_syntax")
+  finish
+endif
+
+" need %{vars}%
+" env: [[CAML_LD_LIBRARY_PATH = "%{lib}%/stublibs"]]
+syn keyword opamKeyword1 remove depends pin-depends depopts conflicts env packages patches version maintainer tags license homepage authors doc install author available name depexts substs synopsis description
+syn match opamKeyword2 "\v(bug-reports|post-messages|ocaml-version|opam-version|dev-repo|build-test|build-doc|build)"
+
+syn keyword opamTodo FIXME NOTE NOTES TODO XXX contained
+syn match opamComment "#.*$" contains=opamTodo,@Spell
+syn match opamOperator ">\|<\|=\|<=\|>="
+
+syn region opamInterpolate start=/%{/ end=/}%/ contained
+syn region opamString start=/"/ end=/"/ contains=opamInterpolate
+syn region opamSeq start=/\[/ end=/\]/ contains=ALLBUT,opamKeyword1,opamKeyword2
+syn region opamExp start=/{/ end=/}/ contains=ALLBUT,opamKeyword1,opamKeyword2
+
+hi link opamKeyword1 Keyword
+hi link opamKeyword2 Keyword
+
+hi link opamString String
+hi link opamExp Function
+hi link opamSeq Statement
+hi link opamOperator Operator
+hi link opamComment Comment
+hi link opamInterpolate Identifier
+
+let b:current_syntax = "opam"
+
+" vim: ts=2 sw=2