Changes

  *  The functions slot in ScriptNodeInfo is now a logical vector with the names identifying the functions.
     The logical values are used to indicate if the functions is defined within a task in the script (TRUE, 
     if this is unknown (NA), or if it is externally defined (FALSE).

0.3-0 

  *   Read Sweave files via knit() in knitr.

  *   Processing of TeX's \inputs (and \endinput).

  *   readJSS() and TeX generally more flexible.

  *   historyAsScript().

0.2-1

  *   Computing the time-line avoids duplicate variables.

  *   Time-line plot has better default for the margins so that variable names appear
      more completely.

0.2-0

  *  Added parameters inputs and free to getVariables() and makeVariableGraph() to allow 
     free/global variables in the graph.

  *  Introduced the notion of update variables for a task/expression as an extension
     of inputs and outputs. These are variables whose contents are assigned values
     via expressions such as names(x) = ..., x$foo = ... and so on.

  *  Documented runUpToSection() and changed the default value for all to TRUE.