feat(upgrade): implement in-place self-upgrade command and bump version to v0.6.0

Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "sanctum"
-version = "0.5.0"
+version = "0.6.0"
 edition = "2021"
 authors = ["Harald Pansi <harald@pansi.eu>", "Sanctum Engineering Team"]
 description = "Verschlüsselter Ein-Datei-Container unter Windows im reinen Userland via WebDAV"
@@ -36,6 +36,10 @@ dyn-clone = "1.0"
 lz4_flex = "0.11"
 bip39 = { version = "2.2", features = ["zeroize"] }
 hex = "0.4"
+self-replace = "1.5"
+ureq = { version = "2.10", default-features = false, features = ["json", "tls"] }
+sha2 = "0.10"
+semver = "1.0"
 
 [target.'cfg(windows)'.dependencies]
 tray-item = "0.10"