- This greatly reduces the duplicated functions needed between F# and C#; F# lists satisfy the sequence reqs
- Swap howMatched and fields throughout - Existing tests pass; still need new ones for byFields
- Implements `Field` type for by-field actions (**BREAKING**) - Adds `RemoveFields*` functions/methods for removing fields from documents
This encompasses: - New behavior for SQLite - Migrated behavior for PostrgeSQL (from BitBadger.Npgsql.FSharp.Documents) - New "byField" behavior for PostgreSQL - A unification of C# and F# centric implementations
