add bindings and fix documentation

Package.swift

@@ -0,0 +1,41 @@
+// swift-tools-version:5.3
+
+import Foundation
+import PackageDescription
+
+var sources = ["src/parser.c"]
+if FileManager.default.fileExists(atPath: "src/scanner.c") {
+    sources.append("src/scanner.c")
+}
+
+let package = Package(
+    name: "TreeSitterDjango",
+    products: [
+        .library(name: "TreeSitterDjango", targets: ["TreeSitterDjango"]),
+    ],
+    dependencies: [
+        .package(url: "https://github.com/tree-sitter/swift-tree-sitter", from: "0.10.0"),
+    ],
+    targets: [
+        .target(
+            name: "TreeSitterDjango",
+            dependencies: [],
+            path: ".",
+            sources: sources,
+            resources: [
+                .copy("queries")
+            ],
+            publicHeadersPath: "bindings/swift",
+            cSettings: [.headerSearchPath("src")]
+        ),
+        .testTarget(
+            name: "TreeSitterDjangoTests",
+            dependencies: [
+                .product(name: "SwiftTreeSitter", package: "swift-tree-sitter"),
+                "TreeSitterDjango",
+            ],
+            path: "bindings/swift/TreeSitterDjangoTests"
+        )
+    ],
+    cLanguageStandard: .c11
+)