Fix a typo: compatability -> compatibility

src/gevent/_ssl2.py

@@ -431,6 +431,6 @@ def get_server_certificate(addr, ssl_version=PROTOCOL_SSLv23, ca_certs=None):
 
 def sslwrap_simple(sock, keyfile=None, certfile=None):
     """A replacement for the old socket.ssl function.  Designed
-    for compatability with Python 2.5 and earlier.  Will disappear in
+    for compatibility with Python 2.5 and earlier.  Will disappear in
     Python 3.0."""
     return SSLSocket(sock, keyfile, certfile)