More Changes to usefulchem-molecules Feed and CMLRSSReader

Recent changes to the usefulchem-molecules feed and CMLRSSReader:

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Menu programs can now be added to both the Feed and Item menus, via entries in the configuration file.  These entries have the form

  <MenuPrograms>
    <FeedPrograms>
      <FeedProgram>
        <RunString></RunString>
        <MenuName></MenuName>
      </FeedProgram>
      <FeedProgram>
        <RunString></RunString>
        <MenuName></MenuName>
      </FeedProgram>
    </FeedPrograms>
    <ItemPrograms>
      <ItemProgram>
        <RunString></RunString>
        <MenuName></MenuName>
      </ItemProgram>
    </ItemPrograms>
  </MenuPrograms>

These programs receive as respective parameters the saved (Java serialized) feed and item files, and can use the APIs in the CMLRSSReader software to read these files.  For an example, run the software with Run.Menu.bat instead of Run.bat.

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Flexibility has been added in the content displayed in the item pages.  Instead of displaying all the molecule fields in a feed, specified fields can be omitted.  This is desirable when a field contains data not suitable for display; for example, the text of a blog (which is now, in fact, contained in the usefulchem-molecules feed).  Also, instead of displaying molecule fields, the <description> contained in the item can displayed instead; or both (or neither!) can be displayed.  The configuration entries are

  <IncludeItemDescription></IncludeItemDescription>
  <IncludeMoleculeFields></IncludeMoleculeFields>
  <OmittedFields>
    <OmittedField></OmittedField>
    <OmittedField></OmittedField>
  </OmittedFields>

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The entries in the <PostDownload> and <PostProcess> hooks should now be file names containing a list of programs to be run, not the programs themselves.  This gives greater flexibility in configuring these programs.  Finally, another hook has been added, the <Cycle> hook.  This hook runs whenever CMLRSSReader checks a feed, regardless of whether a new version of the feed is downloaded and processed or not.