Efcore.pg: EF Core 2.2 issues that require Npgsql action

[roji]

See https://github.com/aspnet/EntityFramework.Docs/pull/904 for more, arrange them in the following lists...

• [x] https://github.com/aspnet/EntityFrameworkCore/pull/12057 (Allow customizable SQL delimeters in tests )
• [x] https://github.com/aspnet/EntityFrameworkCore/issues/12044 (DbFunction tests)
• [x] https://github.com/aspnet/EntityFrameworkCore/issues/12001 (transaction test issue)
• [x] https://github.com/aspnet/EntityFrameworkCore/issues/11940 (Abstract SQL delimeters in tests)
• [x] https://github.com/aspnet/EntityFrameworkCore/pull/12666 (unify logging test infrastructure)
• [x] https://github.com/aspnet/EntityFrameworkCore/pull/11978 (simplify type mapping clone methods)
• [x] https://github.com/aspnet/EntityFrameworkCore/pull/13035 (new plugin API)
• [x] https://github.com/aspnet/EntityFrameworkCore/issues/13764 (generate use plugin when scaffolding)

Punted to 3.0:
https://github.com/aspnet/EntityFrameworkCore/issues/1679 (view support, scaffolding)
https://github.com/aspnet/EntityFrameworkCore/issues/8427 (parameterless UseNpgsql)
https://github.com/aspnet/EntityFrameworkCore/issues/11896 (facets in store type names)

[roji]

For anyone interested (e.g. @austindrenski), I have a branch where I'm working on synchronizing our dev branch with the latest EF Core 2.2 codebase (https://github.com/roji/Npgsql.EntityFrameworkCore.PostgreSQL/tree/2.2). This "resynchronization" has to be done from time to time as the EF Core team at Microsoft moves ahead, especially to flag early anything they do that may be problematic for PostgreSQL.

Once I have a version with all the tests passing, I'll merge to dev.

[roji]

This is complete AFAIK, we're building and testing successfully against the pre-RTM 2.2.0.