Added ignore files

Author: KumarVivek

.gitignore

@@ -13,3 +13,7 @@ settings.json
 /.vs/slnx.sqlite
 /.vs/powerapps-docs-pr/v16/.suo
 /.vs/VSWorkspaceState.json
+powerapps-docs/.vs/powerapps-docs/v15/.suo
+powerapps-docs/.vs/ProjectSettings.json
+powerapps-docs/.vs/slnx.sqlite
+powerapps-docs/.vs/VSWorkspaceState.json