Bump version for release.

NEWS

@@ -1,4 +1,4 @@
-1.3.15.dev0
+1.3.15
  * #208: Fix for traceback when the "checks" option has an empty value.
  * #209: Bypass Borg error about a moved repository via "relocated_repo_access_is_ok" option in
    borgmatic storage configuration section.

setup.py

@@ -1,6 +1,6 @@
 from setuptools import find_packages, setup
 
-VERSION = '1.3.15.dev0'
+VERSION = '1.3.15'
 
 
 setup(