Add precedence and associativity
Start with the conversion from js/cc to jison
Add jison to package.json
Use the new parser
Rewrote the grammar
Adjust the interpreter to changes of the AST
Use the dev version of jessiecode in all of the examples
Tracking a bug
Finish the grammar
Remove now obsolete utf8 handling
Fix several bugs related to the ParamList->ElementList changes
Remove unused nodes from the interpreter
Simplify snippet()
Fix several bugs regarding the ParamDef->ElementList conversion
Fix unary minus operator
Extend the grammar to parse maps

A map is like a function but restricted to math expressions, e.g.

    f = (x) -> 3*(sin(x) + cos(x));

On the right hand side of the map operator -> arithmetic math expressions with identifiers, numbers and calls of other maps (if none or at least one of the map parameters is involved) or functions (if none of the map parameters is involved) are allowed.

Maps will be used to symbolically determine the derivative and antiderivative of a mathematical expression.

Maps can not be nested.
Fix chained assignments
Replace make.py with Makefile