Typeset maths support for more standard functions

• Remember the directory used in the filechooser.
• Always decode non-ASCII characters from the pop-up keyboard and from templates to their correct REDUCE or TeX names.
• Replace loading the fmprint package with inputting and compiling the new source file "rrprint.red" contained in the JAR file, which is based on "tmprint.red".
• Typeset maths improvements:
  • Apply the fix by Eberhard Shruefer so that order commands work.
  • Output identifiers in mathit instead of mathrm style.
  • Correct spacing of := and leading + and - signs.
  • Display a trailing multiplication sign but otherwise ignore multiplications. (This may be too drastic.)
  • Support all trigonometric and hyperbolic functions and their inverses, and logb and log10.
  • Display the gamma function, but not the identifier gamma, using a capital Gamma.
  • Support the polygamma, iGamma, iBeta, dilog, Pochhammer and integral functions.
  • Support Airy and Hankel functions.
  • Support Struve, Lommel, Kummer, Whittaker and spherical harmonic functions, and the classical orthogonal polynomials.