Add a debugger token to SetTraceVariables and GetTraceVariables to prevent crash an inconsistant data in case of multiple connections. Last connection now takes over existing connections's debug, and first connected IDE gets a wrning.

          <xsd:attribute name="Command" type="xsd:string" use="optional" default="make -C %(buildpath)s all BEREMIZSRC=%(src)s BEREMIZCFLAGS=%(cflags)s MD5=%(md5)s USE_BEREMIZ=1 FROM_BEREMIZ=1"/>