Level 0 Section

inputfilespecifies the input template file (may include substitutions)
outputfilespecifies the output file (may include substitutions)
appendspecifies that the output should be appended to existing file
multipassspecifies that the input template may be used in different passes. Content before the header and after the footer is ignored.
dxfmodespecifies special processing for DXF files
headerstring that marks the start of the section to be processed
footerstring that marks the end of the section to be processed
symbolspecifies a symbol for this level to iterate on