usingDirectivesPlacement should be ignored unless fixing SA1200

[sharwell]

Currently the using directives code fix uses the current usingDirectivesPlacement setting when organizing using directives for any supported diagnostic. This behavior will not correctly handle cases where diagnostic suppressions are used to disable particular instances of SA1200.

To correct this issue, the code fix should operate as though usingDirectivesPlacement were set to ignore when fixing any diagnostic other than SA1200.

Example code

using System;
using System.Reflection;
using System.Net;

namespace MyNamespace
{
    using System.ServiceModel.Channels;
}

Operation

Fix all violations of SA1210.

Expected result

using System;
using System.Net;
using System.Reflection;

namespace MyNamespace
{
    using System.ServiceModel.Channels;
}

Actual result

using System;
using System.Net;
using System.Reflection;
using System.ServiceModel.Channels;

namespace MyNamespace
{
}

[vweijsters]

Grabbing this