Function install 

pub fn install(
    packs: &mut PackRegistry,
    config: Value,
) -> Result<(), InstallError>

The Plugin: inserts the web Pack into packs with config["web"], which is null when config has no web key.

Errors

Returns the registry’s [InstallError], such as [InstallError::DuplicatePack] when packs holds runvil/web already.