pre-upload: drop support for Python 3.4

We've been emitting warnings about this for ~6 months, and our pylint
helper actually already requires Python 3.5, so require it in the main
script now too.

We still emit warnings for Python 3.5 being deprecated.

Bug: None
Test: `repo upload` still works w/Python 3.6
Change-Id: Ib78d3d6d082ba9bfd1a26ac582a93f1f088b304f
diff --git a/pre-upload.py b/pre-upload.py
index 0d0afb6..57f699b 100755
--- a/pre-upload.py
+++ b/pre-upload.py
@@ -34,9 +34,8 @@
 if sys.version_info < (2, 7, 5):
     print('repohooks: error: Python-2.7.5+ is required', file=sys.stderr)
     sys.exit(1)
-elif sys.version_info.major == 3 and sys.version_info < (3, 4):
-    # We don't actually test <Python-3.6.  Hope for the best!
-    print('repohooks: error: Python-3.4+ is required', file=sys.stderr)
+elif sys.version_info.major == 3 and sys.version_info < (3, 5):
+    print('repohooks: error: Python-3.5+ is required', file=sys.stderr)
     sys.exit(1)
 elif sys.version_info < (3, 6):
     # We want to get people off of old versions of Python.