list items must be able to start with asterisk

immediately followed by a non-space character. This allows emphasised
texts to start lists items and must fix issue #120

Author: lyokha

syntax/pandoc.vim

@@ -420,7 +420,7 @@ syn match pandocListItem /^\s*(\?x\=l\=\(i\{,3}[vx]\=\)\{,3}c\{,3}[.)].*$/ nextg
 syn match pandocListItemBullet /^(\?.\{-}[.)]/ contained containedin=pandocListItem
 syn match pandocListItemBulletId /\(\d\+\|\l\|\#\|@.\{-}\|x\=l\=\(i\{,3}[vx]\=\)\{,3}c\{,3}\)/ contained containedin=pandocListItemBullet
 
-syn match pandocListItemContinuation /^\s\+\(\([-+*]\|(\?.\+[).]\)\@<![[:alpha:]ñäëïöüáéíóúàèìòùłßÄËÏÖÜÁÉÍÓÚÀÈÌÒÙŁß_"[]\)\@=.*$/ nextgroup=pandocLaTeXMathBlock,pandocLaTeXInlineMath,pandocDelimitedCodeBlock,pandocListItemContinuation,pandocListItem contains=@Spell,pandocEmphasis,pandocStrong,pandocNoFormatted,pandocStrikeout,pandocSubscript,pandocSuperscript,pandocStrongEmphasis,pandocStrongEmphasis,pandocPCite,pandocICite,pandocCiteKey,pandocReferenceLabel,pandocReferenceURL,pandocLaTeXMathBlock,pandocLaTeXInlineMath,pandocAutomaticLink contained skipempty display 
+syn match pandocListItemContinuation /^\s\+\(\([-+*]\s\+\|(\?.\+[).]\)\@<![[:alpha:]ñäëïöüáéíóúàèìòùłßÄËÏÖÜÁÉÍÓÚÀÈÌÒÙŁß_\-+*"[]\)\@=.*$/ nextgroup=pandocLaTeXMathBlock,pandocLaTeXInlineMath,pandocDelimitedCodeBlock,pandocListItemContinuation,pandocListItem contains=@Spell,pandocEmphasis,pandocStrong,pandocNoFormatted,pandocStrikeout,pandocSubscript,pandocSuperscript,pandocStrongEmphasis,pandocStrongEmphasis,pandocPCite,pandocICite,pandocCiteKey,pandocReferenceLabel,pandocReferenceURL,pandocLaTeXMathBlock,pandocLaTeXInlineMath,pandocAutomaticLink contained skipempty display 
 " }}}
 " Definitions: {{{2
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