Update version.

src/ZEO/__init__.py

@@ -22,4 +22,4 @@ ZEO is now part of ZODB; ZODB's home on the web is
 """
 
 # The next line must use double quotes, so release.py recognizes it.
-version = "3.7.0a0"
+version = "3.7.0b1"

src/ZEO/version.txt

-3.7.0a0
+3.7.0b1

src/ZODB/__init__.py

@@ -13,7 +13,7 @@
 ##############################################################################
 
 # The next line must use double quotes, so release.py recognizes it.
-__version__ = "3.7.0a0"
+__version__ = "3.7.0b1"
 
 import sys