Set next version to a `dev` once again

Signed-off-by: Ulysses Souza <[email protected]>

compose/__init__.py

@@ -1,4 +1,4 @@
 from __future__ import absolute_import
 from __future__ import unicode_literals
 
-__version__ = '1.26.0'
+__version__ = '1.27.0dev'