SVN::Dumpfile::Node::Properties - Represents the properties of a
    node in a Subversion dumpfile.
Objects of this class are used in SVN::Dumpfile::Node objects, but
    can also be used independently for manipulating Subversion revision property
    files.
    use SVN::Dumpfile::Node:Properties;
    my $prop = new SVN::Dumpfile::Node::Properties;
    $prop->load('filename');
    ...
    $prop->save('filename');
  - new()
- Returns a new SVN::Dumpfile::Node::Properties object. Properties can be
      given as hash reference, array reference or as a list. Array or list must
      be even an hold key/value pairs and must be used if the order of the given
      properties should be maintained.
- number()
- Returns the number of properties.
- add('property',
    $value)
- add('property',
    $value, $position)
- Adds the property with the given value at given position or at the end.
      Order of properties is maintained to support the creation of identical
      output files.
- del('property')
- Deletes a property from the instance. Note if the properties are written
      in differential form the property will retrain its value from the last
      changed revision when not written. Use mark_deleted() to mark the
      property as deleted in this case.
- mark_deleted('property')
- Marks a property as deleted. This is for differential property blocks
      which are only supported in dumpfile version 3 or later. It automatically
      calls del() on the property.
- unmark_deleted('property')
- Unmarks a property as deleted. This is for differential property blocks
      which are only supported in dumpfile version 3 or later. The property is
      not added to the node, use add() to do this.
- is_deleted('property')
- Returns if a property is marked as deleted. See also
      mark_deleted().
- list_deleted()
- Returns an array of all properties currently marked as deleted. See also
      mark_deleted.
- parse($stringref)
- Internal method to parse single property format element from string. The
      element is removed from the string and returned as (ID, value) pair.
- from_string('string')
- Reads the properties from string by repeatly calling parse().
- read($filehandle,
    $length)
- Reads <length> bytes from filehandle and parses them as properties
      by calling from_string().
- write($filehandle)
- Writes the properties in subversion dumpfile format to the given
      filehandle.
- load($filename)
- load($filehandle)
- Loads the properties from a subversion revision property file.
- save($filename)
- save($filehandle)
- Saves the properties to a subversion revision property file.
- length()
- Returns the length of the string returned by as_string().
- as_string()
- as_string(1)
- to_string()
- to_string(1)
- Returns all properties as one string formatted in the format needed for
      subversion dumpfiles. If a true value is given as argument the format is
      that of subversion revision property files is used ('END' instead of
      'PROPS-END').