Log Message:
Update net/erlang-xmpp to 1.1.13.

Version 1.1.13

- Add XEP-0357 to supported extensions list

Version 1.1.12

- Support XEP-0357: Push Notifications

Version 1.1.11

- Use fast_xml-1.1.23
- Use stringprep-1.0.9

Version 1.1.10

- Add jid support in muc_unsubscribe and muc_subscribe
- Add ?stanza_type, ?stanza_from and ?stanza_to macros
- Remove unused p1_stream extension
- Clarify the library's main idea
- Encode/decode muc_unsubscribe JIDs
- Add support for HTTP File Upload, version 0.3.0
- Makefile: Add dependencies for spec/xdata targets
- Add nif function jid:string_to_usr and use it
- Fix return value from xmpp:start
- Make multiple calls to jid:start() not generate nif reload error