bug fix for xtaci#82

optimized msb with http://graphics.stanford.edu/~seander/bithacks.html

optimize msb() function to de bruijin sequence

fix typos

trigger waitRead to return in SetReadDeadline

OpenStream should return false if read has error issue#61

hide unused api

add comments

Squashed commit of the following:

commit 4d53a56
Author: xtaci <[email protected]>
Date:   Sat Dec 28 22:14:17 2019 +0800

    add function PeekSize

commit 9ca9c83
Author: xtaci <[email protected]>
Date:   Sat Dec 28 21:53:41 2019 +0800

    add Peak

Squashed commit of the following:

commit 4d53a56
Author: xtaci <[email protected]>
Date:   Sat Dec 28 22:14:17 2019 +0800

    add function PeekSize

commit 9ca9c83
Author: xtaci <[email protected]>
Date:   Sat Dec 28 21:53:41 2019 +0800

    add Peak