Grin: When compiling Grin, there are deprecation warnings

[jeffbarg]

When compiling grin, there are a few warnings that come up due to a dependency being deprecated. I'm using Rust stable (cargo 1.29.0 (524a578d7 2018-08-05), rustc 1.29.1 (b801ae664 2018-09-20))

I've pasted the warnings I'm seeing here:

warning: use of deprecated item 'util::secp256k1zkp::aggsig::sign_single': All aggsig-related api functions need review and are subject to change.
  --> wallet/src/libtx/aggsig.rs:44:12
   |
44 |     let sig = aggsig::sign_single(
   |               ^^^^^^^^^^^^^^^^^^^
   |
   = note: #[warn(deprecated)] on by default

warning: use of deprecated item 'util::secp256k1zkp::aggsig::sign_single': All aggsig-related api functions need review and are subject to change.
  --> wallet/src/libtx/aggsig.rs:96:12
   |
96 |     let sig = aggsig::sign_single(
   |               ^^^^^^^^^^^^^^^^^^^

warning: use of deprecated item 'util::secp256k1zkp::aggsig::sign_single': All aggsig-related api functions need review and are subject to change.
   --> wallet/src/libtx/aggsig.rs:178:12
    |
178 |     let sig = aggsig::sign_single(secp, &msg, skey, None, None, None, pubkey_sum, None)?;
    |               ^^^^^^^^^^^^^^^^^^^

d   Compiling grin_servers v0.4.0 (f

[hashmap]

This is intentional, @yeasplume added it as a reminder that this code is security-critical but was written by a non-cryptographer. I assume he will remove it closer to the mainnet launch.