message: Fix macrocode highlighting
  We handle unbalanced code within macrocode environments and comments are
  highlighted with '%' and not '^^A'.
diff: <key>name</key>
  <string>meta.function.verb.latex</string>
  </dict>
  + <dict>
  + <key>match</key>
  + <string>^% \\end\{macrocode\}</string>
  + <key>name</key>
  + <string>support.class.dtx</string>
  + </dict>
  <dict>
  <key>begin</key>
  <string>^% (\\begin\{macrocode\})</string>
  <string>^% (\\end\{macrocode\})(?:\s*\n)?</string>
  <key>patterns</key>
  <array>
  + <dict>
  + <key>match</key>
  + <string>%.*$\n</string>
  + <key>name</key>
  + <string>comment.line.percentage.tex</string>
  + </dict>
  + <dict>
  + <key>match</key>
  + <string>\^\^A.*\n$</string>
  + </dict>
  <dict>
  <key>include</key>
  <string>$base</string>
  