Quote password in URL

By default, the username and password are passed to each request to
the API using Basic authentication. From the `xmlrpc.client` doc:

```
Both the HTTP and HTTPS transports support the URL syntax extension for
HTTP Basic Authentication: http://user:pass@host:port/path. The user:pass
portion will be base64-encoded as an HTTP ‘Authorization’ header, and sent
to the remote server as part of the connection process when invoking an
XML-RPC method.
```

So this lib generate an URL containing the username and the password. If
the password contained some characters (cf
https://datatracker.ietf.org/doc/html/rfc3986.html#section-2.2), the URL
became invalid. By simply using `urllib.parse.quote` on the password,
the problem is solved.

From a quick test, Dokuwiki seems to remove special characters from
username so only the password requires quoting.

Setting the `cookieAuth` parameter would have prevented the problem. When
set, the session is kept using cookies (via the HTTP headers) and only
one call to the *login* endpoint is done (and the password is not
wrappred in the URL).

Fix #24

Author: fmenabe

dokuwiki.py

@@ -24,10 +24,10 @@
 PY_VERSION = sys.version_info[0]
 if PY_VERSION == 3:
     from xmlrpc.client import ServerProxy, Binary, Fault, Transport, SafeTransport, ProtocolError
-    from urllib.parse import urlencode
+    from urllib.parse import quote
 else:
     from xmlrpclib import ServerProxy, Binary, Fault, Transport, SafeTransport, ProtocolError
-    from urllib import urlencode
+    from urllib import quote
 
 from datetime import datetime, timedelta
 
@@ -154,7 +154,7 @@ def __init__(self, url, user, password, **kwargs):
             raise DokuWikiError("invalid url '%s'" %  url)
 
         # Set auth string or transport for cookie based authentication.
-        auth = '{:s}:{:s}@'.format(user, password)
+        auth = '{:s}:{:s}@'.format(user, quote(password))
         cookie_auth = kwargs.pop('cookieAuth', False)
         if cookie_auth:
             auth = ''