feature #10: log Query

src/main/kotlin/fr/postgresjson/stopwatch/Stopwatch.kt

@@ -0,0 +1,8 @@
+package fr.postgresjson.stopwatch
+
+fun <T> elapse(callback: (start: Long) -> T, after: (elapse: Long) -> Unit): T {
+    val start = System.currentTimeMillis()
+    val result = callback(start)
+    after(System.currentTimeMillis() - start)
+    return result
+}