chart won't re-render when options changed

[hs3180]

tested in v0.0.5

[weizhenye]

See #1
I'm writing tests now and will fix it later.

[hs3180]

works fine on vue 2.x.
this bug can only reproduce on vue 1.x.

vue 2.x's lifecycle is upgraded from vue 1.x and updated stage is implemented since 2.0.

2.x LifeCycle
1.x LifeCycle