Suggestion list cleanups (#115)

* Add additional autocomplete words

* Add another word to default completion list

* Add colorization keywords and fix minor bugs.

src/Microsoft.SqlTools.ServiceLayer/Hosting/ServiceHost.cs

@@ -157,7 +157,7 @@ namespace Microsoft.SqlTools.ServiceLayer.Hosting
                         CompletionProvider = new CompletionOptions
                         {
                             ResolveProvider = true,
-                            TriggerCharacters = new string[] { ".", "-", ":", "\\", "," }
+                            TriggerCharacters = new string[] { ".", "-", ":", "\\" }
                         },
                         SignatureHelpProvider = new SignatureHelpOptions
                         {

src/Microsoft.SqlTools.ServiceLayer/LanguageServices/AutoCompleteHelper.cs

@@ -30,7 +30,7 @@ namespace Microsoft.SqlTools.ServiceLayer.LanguageServices
 
         private static WorkspaceService<SqlToolsSettings> workspaceServiceInstance;
 
-        private static Regex ValidSqlNameRegex = new Regex(@"^[\p{L}_][\p{L}\p{N}@$#_]{0,127}$");
+        private static Regex ValidSqlNameRegex = new Regex(@"^[\p{L}_@][\p{L}\p{N}@$#_]{0,127}$");
 
         private static CompletionItem[] emptyCompletionList = new CompletionItem[0];
 
@@ -103,6 +103,7 @@ namespace Microsoft.SqlTools.ServiceLayer.LanguageServices
             "end-exec",
             "exec",
             "execute",
+            "exists",
             "exit",
             "external",
             "fast_forward",
@@ -177,6 +178,7 @@ namespace Microsoft.SqlTools.ServiceLayer.LanguageServices
             "nonclustered",
             "none",
             "norecompute",
+            "not",
             "now",
             "null",
             "numeric",
@@ -193,6 +195,7 @@ namespace Microsoft.SqlTools.ServiceLayer.LanguageServices
             "or",
             "order",
             "out",
+            "outer",
             "output",
             "over",
             "owner",