Added 'NamedConstant' drag'n'drop in programs. It does create a simple variable with initial value and is usefull for drag'n'drop constants from extensions while keeping a name associated with constant
<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"/>