DB and OMEMO rework

[COM8]

This PR aims to rework the DB as well as update to OMEMO 0.7.0.
Tasks:

• Create a own OMEMO library for OMEMO 0.7.0. New updated OMEMO spec Version 0.7.0 #126 (Code)
• Refactor and replace the whole DB from sqlite-net-pcl to Entity Framework Core Replace sqlite-net-pcl with something else #55.
• Fix UI update events
• Fix TPH not loading values
• Fix SignedPreKeyModel not generating DB table correctly
• Thoroughly test the new DB backend
• Fix adding a duplicate account crash
• Fix MAM prcessing, trigger the complete message stack
• Old MAM messages can contain chat state updates. Add a way to determin if the chat state is newer than the one we received last.
• Fix OMEMO fingerprints getting replaced
• Do not request the FULL message archive, but instead for example only the last month or so.
• Fix MAM retrival order from oldest to newest.
• Fix MUC info page crash when a lot of members join/leave.
• Fix presence is on Unavailable by default.
• Fix chat message list has duplicate entries.
• Add a way to disable OMEMO trusted keys only in code. UI part is already done.
• Fix changing device label should update the device list.
• Fix OMEMO foreign key exception when storing a session.
• Fix chat list reset on moving item