Move version to a separate file. Fix oleiade#50

In order to get the current version, the setup was importing
py-elevator. This was causing an issue as the depencencies were
not installed yet.
Now the version is in its own file, and is imported in __init__.py
and setup.py.

pyelevator/__init__.py

@@ -4,13 +4,11 @@
 #
 # See the file LICENSE for copying permission.
 
-version = (0, "5c")
+from version import version, __version__
 
 __title__ = "py-elevator"
 __author__ = "Oleiade"
 __license__ = "MIT"
 
-__version__ = '.'.join(map(str, version))
-
 from .client import Elevator
 from .batch import WriteBatch

pyelevator/version.py

@@ -0,0 +1,2 @@
+version = (0, "5c")
+__version__ = '.'.join(map(str, version))

setup.py

@@ -2,11 +2,12 @@
 # -*- coding: utf-8 -*-
 
 import os
+import imp
 from setuptools import setup
 
 root = os.path.abspath(os.path.dirname(__file__))
 
-version = __import__('pyelevator').__version__
+version = imp.load_source('', 'pyelevator/version.py').__version__
 
 with open(os.path.join(root, 'README.rst')) as f:
     README = f.read()
@@ -16,7 +17,7 @@
     version=version,
     license='MIT',
 
-    description = 'Python client for on-disk key/value database Elevator',
+    description='Python client for on-disk key/value database Elevator',
     long_description=README,
 
     author='Oleiade',