Feature execution plan settings and request implementation (#213)

* experimental showplan implementation (tools side only)

* fix for redundant massages from showplan executions

* moved showplan batches to new variables to make it less confusing

* returns showplan as part of batch summary with in each result summary

* cleaned up showplan resultsets

* cleaning up code and making showplan var optional

* changes all var names to showplan

* adding estimated support

* small fixes

* updatin var names and adding EPOptions struct

* adding ssms execution plan logic based on server types

* adding special actions logic

* removing redundant name changes

* execution plan query handler added

* cleaning up functions and data structures

* seperated special actions into its own class

* cleaning up special actions

* cleaning up code

* small new line fixes

* commenting out pre-yukon code

* removing all pre yukon code

* last yukon code commented out

* fixes broken tests

* adding related unit tests; integration tests incoming

* finishing tests and cleaning up code

* semantic changes

* cleaning up semantics

* changes and test fixes, also adding new exceptions into RS

* fixing special actions and cleaning up request logic

* fixing comment to trigger new build

* triggering another  build

* fixed up specialaction and added tests for it

src/Microsoft.SqlTools.ServiceLayer/Connection/ConnectionService.cs

@@ -19,6 +19,7 @@ using Microsoft.SqlTools.ServiceLayer.LanguageServices.Contracts;
 using Microsoft.SqlTools.ServiceLayer.SqlContext;
 using Microsoft.SqlTools.ServiceLayer.Utility;
 using Microsoft.SqlTools.ServiceLayer.Workspace;
+using Microsoft.SqlServer.Management.Common;
 
 namespace Microsoft.SqlTools.ServiceLayer.Connection
 {
@@ -292,6 +293,8 @@ namespace Microsoft.SqlTools.ServiceLayer.Connection
                     OsVersion = serverInfo.OsVersion
                 };
                 connectionInfo.IsAzure = serverInfo.IsCloud;
+                connectionInfo.MajorVersion = serverInfo.ServerMajorVersion;
+                connectionInfo.IsSqlDW = (serverInfo.EngineEditionId == (int)DatabaseEngineEdition.SqlDataWarehouse);
             }
             catch(Exception ex)
             {