implement the rest procedures of `input` but `u8-ready?` is incomlete like `char-ready?`
make `read-bytevector(!)` efficint, export `u8-ready?`.
allow `else` and `=>` keyword in `case`
if `=>` is specified, treat expression as a function
fix analyze errer for (+) and (*)
Merge pull request #116 from KeenS/addmul-arity

Fix analyze errer for (+) and (*)
Merge pull request #115 from KeenS/case-else

allow `else` and `=>` keyword in `case`
resolve confrict
Merge pull request #113 from KeenS/binary-input

implement the rest procedures of `input` but `u8-ready?` is incomlete li...