Added version number to pystencils

Pystencils should have a __version__ attribute

pystencils/__init__.py

@@ -21,6 +21,18 @@ try:
 except ImportError:
     pass
 
+
+def _get_release_file():
+    import os.path
+    file_path = os.path.abspath(os.path.dirname(__file__))
+    return os.path.join(file_path, '..', 'RELEASE-VERSION')
+
+
+try:
+    __version__ = open(_get_release_file(), 'r').read()
+except IOError:
+    __version__ = 'development'
+
 __all__ = ['Field', 'FieldType', 'fields',
            'TypedSymbol',
            'make_slice',