luatexja-fontspec.sty: Changed syntax of AltFont, AltFontFeatures and AltFontRange

luatexja-fontspec.sty: Changed syntax of AltFont, AltFontFeatures and AltFontRange

Example:
\jfontspec[
  AltFont={JJSYuMin5goKn-R,DejaVuSans },
  AltFontFeatures={,{Color=0000FF,JFM=prop }},
  AltFontRange={"3000-"30FF,{"21B3,"21B5 }}%"
]{JJSYuMinchoPr6N-R}

TODO: update documents