Unable to provide #[serde( with = )] instructions

[fnordpig]

When trying to deserialize/serialize something with a custom handler for a field in a struct that needs to be handled by serde (specifically in my case chrono::DateTime encoded with ts_milliseconds), it doesn't work. I had to wrap my DateTime<> members in a wrapper struct that I wrote. Not doing this causes huge performance problems as the default encoding / decoding is string based.

I can provide a working example if desired, but here's a snippet from my code reflecting my workaround:

#[derive(PartialEq, Debug, Serialize, Deserialize, Clone)]
pub struct DateTimeWrapper {
    #[serde(with = "ts_milliseconds")]
    pub time: DateTime<Utc>,
}


#[derive(Debug, Clone, PartialEq,  bincode::Decode, bincode::Encode)]
pub struct Quote {
    #[bincode(with_serde)]
    pub time: DateTimeWrapper,
    pub price: f64,
    pub size: f64
}

I would much rather it be:

#[derive(Debug, Clone, PartialEq,  bincode::Decode, bincode::Encode)]
pub struct Quote {
    #[bincode(with_serde)]
    #[serde(with = "ts_milliseconds")]
    pub time: DateTime<Utc>,
    pub price: f64,
    pub size: f64
}

Thank you for the excellent project by the way, I love the 2.0 can't wait to see it release.