plusminus_0.4.0

plusminus 0.4.0

- Update default sys.setrecursionlimit to 3000 if it has not
  already been modified, to allow for deep call stacks generated
  from infixNotation parsers.

- Custom functions can now take different numbers of arguments,
  using a tuple of integers for the arity. For example, here is the
  log function, that can take only one or two arguments:

      self.add_function("log", (1, 2), math.log)

- Updated operators and functions in ArithmeticParser:

    - "−" can now be used as a unary minus operator, like "-".

    - "//" operator for floor division added.

    - round function now accepts one or two arguments, instead of two only.

- Updated operators, functions and variables in BasicArithmeticParser:

    - Added the log function above in the BasicArithmeticParser. If called
      with one argument, base e is used. If called with two, the second
      argument is used as the base.

    - Removed the nhypot function. The hypot function now takes any number
      of arguments.

    - gamma function now takes one parameter, instead of two.

    - Added variable "tau" (same as "τ"), which is equal to 2×π.

    - Added variables "ϕ" and "phi" (same as "φ", the golden number).

- Updated documentation and examples in the BasicArithmeticParser class.

Thanks to TheOneMusic for his awesome contributions to this release!

- PLANNED FOR 0.5.0

    - Refactoring the parser classes to provide a
      parser for standard Python expressions using standard Python
      operators and builtins, and functions from the math module
      (may limit types to int and float). Will make this parser more
      of a safe drop-in replacement for "eval" without extra bells and
      whistles.

    - Better definition of custom operators, to permit support for
      proper definition of precedence of operations.

    - Update web demo to support selection of different parsers.