Update the NEWS file for the new release

NEWS

@@ -1,5 +1,29 @@
 liblouisxml NEWS -- history of user-visible changes.
 
+* Noteworthy changes in release 2.7.1 (2019-05-07)
+
+This Liblouisutdml release adds a couple of new features and adds
+support for liblouis 3.9.
+
+** New features
+- Add support for liblouis 3.9
+- Add a Dockerfile
+- Add heading supports for opendocument files thanks to Samuel Thibault
+- Support automatic page numbering thanks to Samuel Thibault.
+  LibreOffice documents do not provide explicit page numbers, but
+  provides the pagebreak points, so liblouisutdml can simply count the
+  page numbers.
+- Move math tables from Liblouis to Liblouisutdml thanks to Bert Frees
+
+** Bug fixes
+- Use the prefixed LOG_FOO constants thanks to Christian Egli
+- Fix cross build from source issue
+
+** Other
+- Convert the test suite to a standard Automake Parallel Test Harness
+  thanks to Christian Egli
+- Set the default log level to LOU_LOG_WARN
+
 * Noteworthy changes in release 2.7.0 (2017-09-20)
 
 This Liblouisutdml release finally has support for liblouis 3.0.