Increment version for the python debugger.

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=113579115

Author: b-daniels

src/googleclouddebugger/__init__.py

@@ -29,7 +29,7 @@
 # The major version should only change on breaking changes. Minor version
 # changes go between regular updates. Instances running debuggers with
 # different major versions will show up as two different debuggees.
-__version__ = '1.5'
+__version__ = '1.6'
 
 _flags = None