Integer Expression

Resolves #17
#define YYSTYPE std::string

Resolves #47
Merge pull request #1 from goodmanio/issues/47

#define YYSTYPE std::string
Return AST::Integer

Resolves #17
Merge pull request #52 from goodmanio/issues/17

Integer Expression
k
kk
ok
yep
kkkkkk
woof