Fix typos in Javadoc of FileUtils and related test classes (#833)

Author: mawiesne

src/main/java/org/apache/commons/io/FileUtils.java

@@ -1555,7 +1555,7 @@ public static File getTempDirectory() {
      * WARNING: this method relies on the Java system property 'java.io.tmpdir'
      * which may or may not have a trailing file separator.
      * This can affect code that uses String processing to manipulate pathnames rather
-     * than the standard libary methods in classes such as {@link File}
+     * than the standard library methods in classes such as {@link File}
      *
      * @return the path to the system temporary directory as a String.
      * @since 2.0

src/test/java/org/apache/commons/io/FileUtilsTest.java

@@ -214,7 +214,7 @@ private Path createCircularOsSymbolicLink(final String linkName, final String ta
 
     /**
      * May throw java.nio.file.FileSystemException: C:\Users\...\FileUtilsTestCase\cycle: A required privilege is not held
-     * by the client. On Windows, you are fine if you run a terminal with aadministrator permissions.
+     * by the client. On Windows, you are fine if you run a terminal with administrator permissions.
      *
      * @return The link path.
      */

src/test/java/org/apache/commons/io/FileUtilsWaitForTest.java

@@ -48,7 +48,7 @@ void testIO_488() throws InterruptedException {
             // This will wait (assuming the file is not found)
             assertFalse(FileUtils.waitFor(NOSUCHFILE, seconds), "Should not find file");
             wasInterrupted.set(Thread.currentThread().isInterrupted());
-        }, "commos-io-Test-IO-488-Thread");
+        }, "commons-io-Test-IO-488-Thread");
         thread1.start();
         Thread.sleep(500); // This should be enough to ensure the waitFor loop has been entered
         thread1.interrupt(); // Try to interrupt waitFor

src/test/java/org/apache/commons/io/function/IOIterableTest.java

@@ -91,7 +91,7 @@ void testSpliterator() {
     }
 
     @Test
-    void testUnrwap() {
+    void testUnwrap() {
         assertSame(fixture.list, iterable.unwrap());
         assertSame(fixture.unwrap(), iterable.unwrap());
     }