Add app tokens (secondary passwords) to afford cheaper hashes

Cargo.lock

@@ -1980,6 +1980,7 @@ dependencies = [
  "argon2",
  "getrandom",
  "password-hash",
+ "pbkdf2",
  "rand_core",
 ]
 
@@ -2000,6 +2001,18 @@ version = "1.0.15"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "57c0d7b74b563b49d38dae00a0c37d4d6de9b432382b2892f0574ddcae73fd0a"
 
+[[package]]
+name = "pbkdf2"
+version = "0.12.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "f8ed6a7761f76e3b9f92dfb0a60a6a6477c61024b775147ff0973a02653abaf2"
+dependencies = [
+ "digest",
+ "hmac",
+ "password-hash",
+ "sha2",
+]
+
 [[package]]
 name = "pem-rfc7468"
 version = "0.7.0"
@@ -2459,6 +2472,8 @@ dependencies = [
  "ical",
  "lazy_static",
  "password-auth",
+ "pbkdf2",
+ "rand_core",
  "regex",
  "rstest",
  "rstest_reuse",