Add SPM manifest with a library target

.gitignore

@@ -6,3 +6,4 @@ build
 fmdb.xcodeproj/*.mode1v3
 *.xcodeproj/project.xcworkspace/xcuserdata/
 fmdb.xcodeproj/project.xcworkspace
+.swiftpm

Package.swift

@@ -0,0 +1,25 @@
+// swift-tools-version:5.0
+// The swift-tools-version declares the minimum version of Swift required to build this package.
+
+import PackageDescription
+
+let package = Package(
+    name: "FMDB",
+    products: [
+        // Products define the executables and libraries produced by a package, and make them visible to other packages.
+        .library(name: "FMDB", targets: ["FMDB"]),
+    ],
+    dependencies: [
+        // Dependencies declare other packages that this package depends on.
+        // .package(url: /* package url */, from: "1.0.0"),
+    ],
+    targets: [
+        // Targets are the basic building blocks of a package. A target can define a module or a test suite.
+        // Targets can depend on other targets in this package, and on products in packages which this package depends on.
+        .target(
+            name: "FMDB",
+            dependencies: [],
+            path: "src/fmdb",
+            publicHeadersPath: "."),
+    ]
+)