fixed two non-printable characters that should have been spaces which caused the DynJS parser to malfunction

The file vertx/buffer.js contained non-printable characters at two places. These caused the DynJS parser to not function properly resulting in SyntaxErrors. I fixed the characters using a hex editor and checked it is working properly afterwards.

Notice, the lang-js.jar snapshot available at Sonartype is not functional at the time of writing. I'm running Windows, other OSes might behave differently, eventually eating the characters...