API to parse/split GO statements into batches

首先查看 issue 中描述的 Microsoft.SqlServer.Management.Common.ExecuteBatch 和 GetStatements 的現有用法，以及 issue 4 中連結的討論。定義用於將 T-SQL 分割為批次的受支援公開 API，包括 GO 20、註解和多行字串，然後驗證其結果是否符合預期的 SQL Management Studio 行為。

Per comment on another issue I am opening this to ask for an API in similar effect to this wrapped function:

/// <summary>
/// Split/Parse a TSQL string into batches by the "GO" statement.
/// Mirrors SQL Management Studio's parsing (because it is the same)
/// </summary>
public static List<string> ParseSQLBatches(string tsql)
{
    var batchParser = new Microsoft.SqlServer.Management.Common.ExecuteBatch();
    var ret = batchParser.GetStatements(tsql);
    return ret.Cast<string>().ToList();
}

The reasoning behind this is that we have scripts written by us for schema/data migrations that commonly utilize GO statements in many ways. We can't easily rely on a simplified "Split on bare GO statements outside of comments" due to sometimes having GO 20 or other such fun things, or multi-line strings etc that might have GO in them for unrelated reasons. Although we could write a parser, that SMO provided one that out of the box (as far as we noticed) was identical to SSMS's was very convenient for us. It seems that this exposed class/api that we were relying on was an implementation detail/surface that is going away in an upcoming release. So the ask here is to facilitate at least this minimal API of "given TSQL string, here it is split-and-duplicated-etc into individual batches".