PICKNDX()

  Short:
  ------
  PICKNDX() Allows user to select indexes to open

  Returns:
  --------
  <nSelected> => number of indexes selected

  Syntax:
  -------
  PICKNDX(aIndexes)

  Description:
  ------------
  Allows the user to point and shoot index selection.

  [aIndexes] is an array to fill with index names. It
  can be of any size, including {}. It is set back to {}
  before selection

  Examples:
  ---------
   aIndexes := {}
   nPicked  := pickndx(aIndexes)

  Source:
  -------
  S_PICKND.PRG