Update README.md (databricks#59)

elasped -> elapsed

Author: flyrev

README.md

@@ -1171,18 +1171,18 @@ When there is an existing well-tesed method and it doesn't cause any performance
  val beginNs = System.nanoTime()
  // Do something
  Thread.sleep(1000)
- val elaspedNs = System.nanoTime() - beginNs
+ val elapsedNs = System.nanoTime() - beginNs
 
  // This is WRONG. It uses magic numbers and is pretty easy to make mistakes
- val elaspedMs = elaspedNs / 1000 / 1000
+ val elapsedMs = elaspedNs / 1000 / 1000
 
  // Use the Java TimeUnit API. This is CORRECT
  import java.util.concurrent.TimeUnit
- val elaspedMs2 = TimeUnit.NANOSECONDS.toMillis(elaspedNs)
+ val elapsedMs2 = TimeUnit.NANOSECONDS.toMillis(elaspedNs)
 
  // Use the Scala Duration API. This is CORRECT
  import scala.concurrent.duration._
- val elaspedMs3 = elaspedNs.nanos.toMillis
+ val elapsedMs3 = elaspedNs.nanos.toMillis
  ```
 
 Exceptions: