Renamed optional dependencies get the wrong feature name recorded

[Nemo157]

async-compression 0.3.6 has a tokio-02 and a tokio-03 optional dependency, but these both get recorded and displayed as tokio. Dumping out of the database I see:

{
  ...
  "(all-implementations,\"{futures-io,stream,tokio-02,tokio-03}\")",
  ...
  "(tokio,{})",
  "(tokio,{})",
  ...
}

So all-implementations depends on tokio-02 and tokio-03, but the optional dependencies themselves show tokio.

docs.rs/src/db/add_package.rs

Line 240 in b527df8

.map(|dep| Feature::new(dep.name.clone(), Vec::new()))

Here it needs to take the renamed name (but unfortunately our little cargo-metadata dataset doesn't record this currently).

[almusil]

Since we need the rename, it would be also wise to extend the Feature in database with optional dependency indicator. It will be easier that way to filter etc IMO. WDYT?

[jyn514]

Sure, if you want to do both at once I'd be fine with that.

[jyn514]

Fixed by #1180 I think.

[Nemo157]

Yep, https://docs.rs/crate/async-compression/0.3.7/features shows tokio-02 and tokio-03 headings.