update copyright.txt to include recent kitware authors (#3965)

* update copyright.txt

* Update Copyright.txt

Copyright.txt

@@ -16,12 +16,18 @@ limitations under the License.
 
 The following individuals and institutions are among the Contributors:
 
+* Ana Gainaru <[email protected]>
+* Caitlin Ross <[email protected]>
 * Chuck Atkins <[email protected]>
-* Greg S. Eisenhauer <[email protected]> 
-* William F. Godoy <godoywf@ornl.gov>
+* Greg Eisenhauer <[email protected]>
+* Dmitry Ganyushin <ganyushindi@ornl.gov>
 * Junmin Gu <[email protected]>
 * Norbert Podhorszki <[email protected]>
 * Ruonan (Jason) Wang <[email protected]>
+* Scott Wittenburg <[email protected]>
+* Spiros Tsalikis <[email protected]>
+* V. A. Bolea Sanchez <[email protected]>
+* William F. Godoy <[email protected]>
 
 See version control history for details of individual contributions.