Prepare for 17.0.0 (#615)

* Prepare for 17.0.0

Fix a bunch URLs and account for the non-existance of 16.3.

* Fix codecov link
diff --git a/src/OpenSSL/crypto.py b/src/OpenSSL/crypto.py
index 165f918..b90f0e4 100644
--- a/src/OpenSSL/crypto.py
+++ b/src/OpenSSL/crypto.py
@@ -1538,7 +1538,7 @@
           For example, you can determine if a certificate was valid at a given
           time.
 
-        .. versionadded:: 16.3.0
+        .. versionadded:: 17.0.0
 
         :param datetime vfy_time: The verification time to set on this store.
         :return: ``None`` if the verification time was successfully set.
diff --git a/src/OpenSSL/version.py b/src/OpenSSL/version.py
index 388cf08..0a61385 100644
--- a/src/OpenSSL/version.py
+++ b/src/OpenSSL/version.py
@@ -11,7 +11,7 @@
     "__title__", "__uri__", "__version__",
 ]
 
-__version__ = "16.3.0.dev0"
+__version__ = "17.0.0.dev0"
 
 __title__ = "pyOpenSSL"
 __uri__ = "https://pyopenssl.readthedocs.io/"
@@ -19,4 +19,4 @@
 __author__ = "The pyOpenSSL developers"
 __email__ = "cryptography-dev@python.org"
 __license__ = "Apache License, Version 2.0"
-__copyright__ = "Copyright 2001-2016 {0}".format(__author__)
+__copyright__ = "Copyright 2001-2017 {0}".format(__author__)