Don't make major version bump after all.

NEWS

@@ -1,4 +1,4 @@
-1.4.0.dev0
+1.3.9.dev0
  * #195: Switch to command-like actions as more traditional sub-commands, e.g. "borgmatic create",
    "borgmatic prune", etc. However, the classic dashed options like "--create" still work!
 

setup.py

@@ -1,6 +1,6 @@
 from setuptools import find_packages, setup
 
-VERSION = '1.4.0.dev0'
+VERSION = '1.3.9.dev0'
 
 
 setup(