Notification icon: Dashed-solid version

Keeping this icon in case it's needed later
Notification icon: Solid version
Updated launcher icon: Bigger circles
Update README.md
Merge branch 'development' of https://github.com/qooob/Conversations into qooob-development
Merge branch 'qooob-development' into development
added rendered versions of new icons
better exception handling in XmppConnection.connect. (never return without throwing exception. use finally to release wake lock. use status.server_not_found instead of status.offline when necessary
better usage of synchronized in some places
disabled broken conversations context menu
properly remove conversations context menu
show dynamic tags in contacts activity as well
synchronized message list in conversation fragment
simplified message merge condition
put error notification into notification service
added faq for srv records
Update spanish translations
Update spanish translations
Update german translations
Update basque translation