Implement lookup

[Bios-Marcel]

APIL:

type TrashedFileInfo interface {
    AbsPath() string
    DeletionDate() time.Time
}

// Lookup checks whether there is any file with a matching path. The path can
// be relative or absolute. Since a path can be deleted multiple times,
// resulting in multiple trashed versions, the return value is an array. If
// the error is empty, there were no matches, in which case the `error` will
// be `nil`.
func Lookup(path string) ([]*TrashedFileInfo, error) {
    // ....
}

The interface TrashedFileInfo allows to have more concrete implementations, allowing the user to extract more information where required and possible, but still allow us to cross compile when using the bare minimum.

[Bios-Marcel]

Implemented in v2

Instead there's a Query function that comes with a Restore() function of the returned object.