Add syntax files from upstream vim repository

syntax/rcs.vim

@@ -0,0 +1,67 @@
+if !exists('g:polyglot_disabled') || index(g:polyglot_disabled, 'vim') == -1
+  
+" Vim syntax file
+" Language:     RCS file
+" Maintainer:   Dmitry Vasiliev <dima at hlabs dot org>
+" URL:          https://github.com/hdima/vim-scripts/blob/master/syntax/rcs.vim
+" Last Change:  2012-02-11
+" Filenames:    *,v
+" Version:      1.12
+
+" Options:
+"   rcs_folding = 1   For folding strings
+
+" quit when a syntax file was already loaded.
+if exists("b:current_syntax")
+  finish
+endif
+
+" RCS file must end with a newline.
+syn match rcsEOFError   ".\%$" containedin=ALL
+
+" Keywords.
+syn keyword rcsKeyword  head branch access symbols locks strict
+syn keyword rcsKeyword  comment expand date author state branches
+syn keyword rcsKeyword  next desc log
+syn keyword rcsKeyword  text nextgroup=rcsTextStr skipwhite skipempty
+
+" Revision numbers and dates.
+syn match rcsNumber "\<[0-9.]\+\>" display
+
+" Strings.
+if exists("rcs_folding") && has("folding")
+  " Folded strings.
+  syn region rcsString  matchgroup=rcsString start="@" end="@" skip="@@" fold contains=rcsSpecial
+  syn region rcsTextStr matchgroup=rcsTextStr start="@" end="@" skip="@@" fold contained contains=rcsSpecial,rcsDiffLines
+else
+  syn region rcsString  matchgroup=rcsString start="@" end="@" skip="@@" contains=rcsSpecial
+  syn region rcsTextStr matchgroup=rcsTextStr start="@" end="@" skip="@@" contained contains=rcsSpecial,rcsDiffLines
+endif
+syn match rcsSpecial    "@@" contained
+syn match rcsDiffLines  "[da]\d\+ \d\+$" contained
+
+" Synchronization.
+syn sync clear
+if exists("rcs_folding") && has("folding")
+  syn sync fromstart
+else
+  " We have incorrect folding if following sync patterns is turned on.
+  syn sync match rcsSync    grouphere rcsString "[0-9.]\+\(\s\|\n\)\+log\(\s\|\n\)\+@"me=e-1
+  syn sync match rcsSync    grouphere rcsTextStr "@\(\s\|\n\)\+text\(\s\|\n\)\+@"me=e-1
+endif
+
+" Define the default highlighting.
+" Only when an item doesn't have highlighting yet.
+
+hi def link rcsKeyword     Keyword
+hi def link rcsNumber      Identifier
+hi def link rcsString      String
+hi def link rcsTextStr     String
+hi def link rcsSpecial     Special
+hi def link rcsDiffLines   Special
+hi def link rcsEOFError    Error
+
+
+let b:current_syntax = "rcs"
+
+endif