- Set application and menubar
- Remove deprecated settings

Fixes #8756

- Sort imports correctly (PEP8)

Avatar Refactoring

Closes #8743

See merge request !135

- Add support for Pubsub Avatars
- Dont poll for vCard Updates, only use XEP-0153
- Dont cache vCards
- Store the avatar SHA of roster contacts in the DB
- Store the current SHA of each contact in the Contacts Object
- Move some code into the ConnectionVcard Class

Update setup.py and .gitignore

See merge request !142

Fix deprecation warnings

See merge request !143

add flatpak support

See merge request !83

Replace make_color_string() by Gdk.RGBA method

See merge request !141

AppData: update information

See merge request !139

tim is epoch, time.localtime() a struct_time

Fixes #8752

Fixes #8753

Simplify check_X509.py

See merge request !140

as pyasn1 and pyOpenSSL are required now

Update README

See merge request !138

wget seems to be broken currently on appveyor

When we receive carbons of a conversation, we remove the events once
we receive a carbon from ourself, because that means we anwered from
another device.

This sets these removed messages also as read in the unread_message
table, so they dont popup on restart.