start refactor
init UT
enable travis-ci
add ci status
enable watching Object
litte modify, detach methods
add `Proxy`, watch Array
remove `Proxy`, do not change prototype
add base directive
add demo
add handlers & code style
delay render
complete `add`, `remove` & `completed`
`getValue` support expression
add `edit`
add `computed`
add computed value
add util spec & fix bug
rename file
refactor again, continue `MVP`