Version update

Migration of library to .NET Standard 2.1 + sample app to .NET Core 3.1

package version update

nuget package updates to fix exception using nullable type in UDT (ht…

…tps://datastax-oss.atlassian.net/browse/CSHARP-640)

Merge branch 'master' of https://github.com/lkubis/AspNetCore.Identit…

…y.Cassandra

Updated assembly version

Updated assembly version

updated package version