Fix confusion between zodbtools and zodbtool

The package was named zodbtools from start (see fd6ad1b9 "Start of
zodbtools.git"). However in 66a03ae5 I've made a thinko naming some
parts as zodbtool.

Fix the confusion and name things uniformly as zodbtools.

/reviewed-by TrustMe

setup.py

@@ -25,9 +25,9 @@ setup(
     # zodb cmd ...
     # zodb dump ...
     entry_points= {'console_scripts': [
-                        'zodbanalyze = zodbtool.zodbanalyze:main',
-                        'zodbcmp     = zodbtool.zodbcmp:main',
-                        'zodbdump    = zodbtool.zodbdump:main',
+                        'zodbanalyze = zodbtools.zodbanalyze:main',
+                        'zodbcmp     = zodbtools.zodbcmp:main',
+                        'zodbdump    = zodbtools.zodbdump:main',
                       ]
                   },
 

zodbtool/util.py → zodbtools/util.py

-# zodbtool - various utility routines
+# zodbtools - various utility routines
 # Copyright (C) 2016  Nexedi SA and Contributors.
 #                     Kirill Smelkov <kirr@nexedi.com>
 

zodbtool/zodbcmp.py → zodbtools/zodbcmp.py

@@ -16,7 +16,7 @@ Exit status is 0 if inputs are the same, 1 if different, 2 if error.
 """
 
 from __future__ import print_function
-from zodbtool.util import ashex, inf, nextitem, txnobjv, parse_tidrange, TidRangeInvalid
+from zodbtools.util import ashex, inf, nextitem, txnobjv, parse_tidrange, TidRangeInvalid
 from time import time
 
 # compare two storage transactions

zodbtool/zodbdump.py → zodbtools/zodbdump.py

@@ -17,7 +17,7 @@ txn ...
 """
 
 from __future__ import print_function
-from zodbtool.util import ashex, sha1, txnobjv, parse_tidrange, TidRangeInvalid
+from zodbtools.util import ashex, sha1, txnobjv, parse_tidrange, TidRangeInvalid
 
 
 def zodbdump(stor, tidmin, tidmax, hashonly=False):