Remove many "versionchanged" items that didn't use the official markup,
but just some text embedded in the docs.
Also remove paragraph about implicit relative imports from tutorial.
diff --git a/Doc/library/base64.rst b/Doc/library/base64.rst
index 68a941f..35b61ae 100644
--- a/Doc/library/base64.rst
+++ b/Doc/library/base64.rst
@@ -21,8 +21,7 @@
interface provides for encoding and decoding to and from file-like objects as
well as strings, but only using the Base64 standard alphabet.
-The modern interface, which was introduced in Python 2.4, provides:
-
+The modern interface provides:
.. function:: b64encode(s[, altchars])