Convo XMPP client

Convo is a messaging application designed for feature phones. It follows the XMPP messaging standard which enables decentralised, provider-independent communication, while allowing interaction with other apps and services on the XMPP network. Powered by ConverseJS and based on web technologies, Convo is currently released as an unofficial proof-of-concept app for KaiOS, but has the potential to (in future) be ported to other web-based platforms too. The primary goal of this project is to develop Convo into a fully functional app that forms a viable messaging solution for KaiOS users, and publish it on the official KaiOS Store. Specifically, the plan is to replace the current homegrown UI with a better designed one based on the solid-telekram project, ensure compliance with the basic XMPP Core and IM Compliance Suites (defined in XEP-0479), and expose end-to-end encryption (OMEMO v0.3) functionality currently implemented upstream in ConverseJS. While not a direct goal, the project will also explore the possiblity of running Convo on other platforms, including button-centric platforms like CloudMosa's Cloud Phone (used in some devices by Nokia/HMD) as well as more "traditonal" touchscreen platforms which support webapps like Phosh and Ubuntu Touch.