Log Message:
Upgrade to 4.2.2. New features:
    * New plot styles
          o Histogram
          o Label plots
          o Image data
          o Filled curves
          o Vectors
    * Input from binary data files
    * New plot elements
          o RGB colors
          o Arbitrary rectangles
    * String handling
          o String and text data read from datafiles
          o User-defined string variables, operators, and functions
    * Macros
    * Auto-layout of multiple plots on a page
    * Internal variables
    * New or revised terminal drivers
          o wxt
          o emf
          o gif, jpeg, png
          o postscript
          o ai
          o epslatex, pslatex, pstex
          o windows
    * Canvas size