Only include necessary files in the Cargo package

LICENSE isn't strictly necessary to use libloot as a Cargo dependency, but the code should be distributed with its license.

Cargo.toml

@@ -7,6 +7,14 @@ repository.workspace = true
 edition.workspace = true
 license.workspace = true
 rust-version.workspace = true
+include = [
+    "/src/**/*.rs",
+    "/build.rs",
+    "/Cargo.lock",
+    "/Cargo.toml",
+    "/LICENSE",
+    "/README.md",
+]
 
 [dependencies]
 crc32fast = "1"