Rev to v5.1.2, update changelog

Author: basepi

CHANGELOG.md

@@ -1,12 +1,13 @@
 # Changelog
 
-## Unreleased
-[Check the diff](https://github.com/elastic/apm-agent-python/compare/v5.1.1...master)
+## v5.1.2
+[Check the diff](https://github.com/elastic/apm-agent-python/compare/v5.1.1...v5.1.2)
 
 ### Bugfixes
  * fixed an issue with http server_url and `'VERIFY_SERVER_CERT': False` (#570, #578)
  * fixed instrumenting of psycopg2 when using their context manager interface (#577, #580)
  * fixed zerorpc tests (#581)
+ * fixed to correctly check if gevent has patched threading.local (#579)
 
 ## v5.1.1 
 [Check the diff](https://github.com/elastic/apm-agent-python/compare/v5.1.0...v5.1.1)

elasticapm/version.py

@@ -28,5 +28,5 @@
 #  OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 #  OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
-__version__ = (5, 1, 1)
+__version__ = (5, 1, 2)
 VERSION = ".".join(map(str, __version__))