[omemo] Update CHANGELOG & manifest.ini

omemo/CHANGELOG

-2.5.0 / 2017-11-15
+2.5.1 / 2017-11-21
+- Bug fix
+
+2.5.0 / 2017-11-20
 - Add MAM for MUC decryption
 
 2.4.3 / 2017-11-15

omemo/manifest.ini

 [info]
 name: OMEMO
 short_name: omemo
-version: 2.5.0
+version: 2.5.1
 description: OMEMO is an XMPP Extension Protocol (XEP) for secure multi-client end-to-end encryption based on Axolotl and PEP. You need to install some dependencys, you can find install instructions for your system in the Github Wiki.
 authors: Bahtiar `kalkin-` Gadimov <bahtiar@gadimov.de>
  Daniel Gultsch <daniel@gultsch.de>