moved key_derivation.rs from pbs_datastore to pbs-config/src/key_config.rs

Also moved pbs-datastore/src/crypt_config.rs to pbs-tools/src/crypt_config.rs.
We do not want to depend on pbs-api-types there, so I use [u8;32] instead of
Fingerprint.

pbs-datastore/Cargo.toml

@@ -27,3 +27,4 @@ proxmox = { version = "0.13.0", default-features = false, features = [ "api-macr
 
 pbs-api-types = { path = "../pbs-api-types" }
 pbs-tools = { path = "../pbs-tools" }
+pbs-config = { path = "../pbs-config" }