added readable_state
remove semicolons
added package.lua and init.lua; better directory structure
add stream_writable
small fix in stream_readable
add stream_duplex
call super class's initializer and another small fix
added node.js SHA-1 for reference
add stream_transform
add stream_passthrough
finish stream.lua
stream_readable: better indent
added an example using stream_readable; various fix in stream_readable
added an example using objectMode; more bug fixes
add observable
Merge pull request #2 from virgo-agent-toolkit/songgao/observer

Add Obserable so that stream data can be duplicated
fix function declaration orders in Readable:pipe()
more bug fixes, mostly on state.buffer.length, as well as local functions
bug fix (pre-declare ondrain)
fix type in filename; use process.stdout in example