Add 'noheader' keyword to docs

doc/src/fix_maxent_rdf.rst

@@ -24,15 +24,17 @@ Syntax
 
   .. parsed-literal::
 
-     keyword = *file* or *append* or *outfreq* or *header*
+     keyword = *file* or *append* or *outfreq* or *noheader*
                or *readcoupling* or *scaling* or *volume* or *readlr* or *writecoupling*
-               or *elements*\ :l
+               or *elements*
        *file* arg = filename
          filename = filename to write bias data to
        *append* arg = filename
          filename = filename to append bias data to
        *outfreq* arg = Noutfreq
          Noutfreq = Frequency with which output is written
+       *noheader* arg = None
+         Do not write header to output file
        *readcoupling* arg = couplingfile
          couplingfile = name of the file containing the coupling values
        *volumescaling* args = *expand* or *contract* followed by *kappa*