Implement MySqlDataAdapter

[bgrainger]

DataAdapter, DataTable, DataSet, etc. are being added in netstandard-2.0: dotnet/corefx#12426

This would allow us to implement MySqlDataAdapter in packages targeting netstandard-2.0 or .NET 4.5 (or later).

[hugosmarques]

Hello anyone knows when the MySQLDataAdapter will be available?

[hugosmarques]

@bgrainger when the MySQLDataAdapter will be available?

[bgrainger]

@hugosmarques there is no timeline for when MySqlDataAdapter will be added to this library. (And since it's a netstandard2.0 feature, probably after that's generally available, at the earliest.)

[bgrainger]

Implemented in 0.33.0.