Better PSScriptAnalyzer runspace pool creation

PssaRunspacePoolCreate.cs

        
        private static RunspacePool CreatePssaRunspacePool()
        {
            // Use public but unfriendly APIs to import a PSScriptAnalyzer module with the needed minimum version
            var pssaModuleSpec = new ModuleSpecification(new Hashtable()
            {
                { "ModuleName", PSSA_MODULE_NAME },
                { "ModuleVersion", s_pssaMinimumVersion }
            });

            // Create a base session state with PSScriptAnalyzer loaded
            InitialSessionState sessionState = InitialSessionState.CreateDefault2();
            sessionState.ImportPSModule(new [] { pssaModuleSpec });

            // RunspacePool takes care of queuing commands for us so we do not
            // need to worry about executing concurrent commands
            return RunspaceFactory.CreateRunspacePool(sessionState);
        }