A bunch of work on non local exits/jumps

I've defined a struct frame which has a jmp_buf, a tag, a value and an
enum specificng the type of frame(i.e
block,tagbody,catch,condition,etc..) I also sketched out ideas for how
to write some of the special forms for control transfer stuff, I'm not
sure how i'm going to be able to integrate this into llvm, but I'll
figure something out