Updating version to 4.4.1

Author: ocelotl

CHANGELOG.md

@@ -1,4 +1,9 @@
 CHANGELOG.md
+<a name="4.4.1"></a>
+## [4.4.0](https://github.com/lightstep/lightstep-tracer-python/compare/4.4.0...4.4.1)
+* Truncate LSb
+* Add contributing guide
+
 <a name="4.4.0"></a>
 ## [4.3.0](https://github.com/lightstep/lightstep-tracer-python/compare/4.3.0...4.4.0)
 * Add support for B3 headers