dependency nom v2.2.1 is out of date

[Frankonly]

When I use the latest stable rustc, following warning printed.

warning: the following packages contain code that will be rejected by a future version of Rust:  nom v2.2.1
note: 
To solve this problem, you can try the following approaches:


- Some affected dependencies have newer versions available.
You may want to consider updating them to a newer version to see if the issue has been fixed.

nom v2.2.1 has the following newer versions available: 3.0.0, 3.1.0, 3.2.0, 3.2.1, 4.0.0-alpha1, 4.0.0-alpha2, 4.0.0-beta1, 4.0.0-beta2, 4.0.0-beta3, 4.0.0, 4.1.0, 4.1.1, 4.2.0, 4.2.1, 4.2.2, 4.2.3, 5.0.0-alpha1, 5.0.0-alpha2, 5.0.0-beta1, 5.0.0-beta2, 5.0.0-beta3, 5.0.0, 5.0.1, 5.1.0, 5.1.1, 5.1.2, 6.0.0-alpha1, 6.0.0-alpha2, 6.0.0-alpha3, 6.0.0-beta1, 6.0.0-beta2, 6.0.0-beta3, 6.0.0-beta4, 6.0.0-beta5, 6.0.0, 6.0.1, 6.1.0, 6.1.1, 6.1.2, 6.2.0, 6.2.1, 7.0.0-alpha1, 7.0.0-alpha2, 7.0.0-alpha3, 7.0.0, 7.1.0, 7.1.1, 7.1.2, 7.1.3