adds initial func rule
adds initial core rules
adds initial statement rules
fixes id list is not expression
adds initial expression rules
adds initial literal rules
fixes char_ to char__ due to name confliction
adds core grammar
adds statement grammar
adds expression grammar
adds def of expression trees
adds literal grammar
adds build methods
adds trees member variables
impl tree construct operators
impl program tree
wip impl func tree
adds namespace obj
wip
adds obj string_ and function