[omemo] Update CHANGELOG & manifest.ini

omemo/CHANGELOG

+1.2.1 / 2017-04-15
+- Recognize aesgcm uri scheme
+
 1.2.0 / 2017-04-06
 - Add auth tag to key instead of payload
 - Support decryption of aesgcm:// uri scheme

omemo/manifest.ini

 [info]
 name: OMEMO
 short_name: omemo
-version: 1.2.0
+version: 1.2.1
 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 Gitlab Wiki.
 authors: Bahtiar `kalkin-` Gadimov <bahtiar@gadimov.de>
  Daniel Gultsch <daniel@gultsch.de>