added type tokens
made some  attempts
Merge branch 'master' of https://github.com/oceanhuang/CoZy into feature-functions2
updated codegenerator
fixed merge conflicts
Merge branch 'master' of https://github.com/oceanhuang/CoZy into feature-functions2
functions now work with lists
added return statements to grammar
return statements in code generator
function expressions without return values work woo
more tests
added type checking for formal params
type checking for parameters works wooooo
functions with return statements work woooo
fixed temperature for functions
updated grammar and code generator
fixed bugs with parameters
fixed all the merge conflicts
fixed test 7 to work with function defs
Merge branch 'master' of https://github.com/oceanhuang/CoZy into feature-functions3