Merge pull request #6 from lukechampine/slice-trick

make TypeCheck properly recursive

use reflect.SliceHeader instead of custom type

95.5% test coverage

move TypeCheck to mmm.go

remove BytesOf

use reflect.MakeSlice instead of ArrayOf

check type in NewMemChunk

represent MemChunk with mmap-backed array

combine BytesOf and bytesOf

combine TypeOf and typeOf

remove redundant iotas

remove unused TypeCheck function

more concise type switch

move byte copying code into bytesOf