Improve requires of setup.py for issue1420

Add version constraint on other modules
Use one line constraint for trytond
Remove unused find_packages

setup.py

@@ -2,19 +2,22 @@
 #This file is part of Tryton.  The COPYRIGHT file at the top level of
 #this repository contains the full copyright notices and license terms.
 
-from setuptools import setup, find_packages
+from setuptools import setup
 import re
 
 info = eval(file('__tryton__.py').read())
+major_version, minor_version, _ = info.get('version', '0.0.1').split('.', 2)
+major_version = int(major_version)
+minor_version = int(minor_version)
 
 requires = ['python-dateutil']
 for dep in info.get('depends', []):
     if not re.match(r'(ir|res|workflow|webdav)(\W|$)', dep):
-        requires.append('trytond_' + dep)
-
-major_version, minor_version, _ = info.get('version', '0.0.1').split('.', 2)
-requires.append('trytond >= %s.%s' % (major_version, minor_version))
-requires.append('trytond < %s.%s' % (major_version, int(minor_version) + 1))
+        requires.append('trytond_%s >= %s.%s, < %s.%s' %
+                (dep, major_version, minor_version, major_version,
+                    minor_version + 1))
+requires.append('trytond >= %s.%s, < %s.%s' %
+        (major_version, minor_version, major_version, minor_version + 1))
 
 setup(name='trytond_account',
     version=info.get('version', '0.0.1'),