Refactor startup process for better performance and greater consistancy

This merge request migrates the seperate registration window into the main bulk of the pyre window. the benefits of this are as follows:

• no need for silly scripting in app.py
• seemless automatic switch between register window and chat window

additionally the calls made by the register process are now non blocking just like all of the rest of the calls, simplifying the signald.py code a bit.