Add initial doxfx content

docs/guide/introduction.md

@@ -0,0 +1,17 @@
+# Introduction
+
+> NOTE: The user guide is currently under development and may be missing
+> important information.  If you feel that a particular area is missing or
+> poorly explained, please feel free to file an issue at our [GitHub site](https://github.com/Microsoft/sqltoolsservice/issues)
+
+SQL Tools Service is a tool that provides useful services to code
+editors that need a great PowerShell editing experience.
+
+## The .NET API
+
+The .NET API provides the complete set of services which can be used in
+code editors or any other type of application.
+
+If you're a developer that would like to use PowerShell Editor Services in
+a .NET application, read the page titled [Using the .NET API](using_the_dotnet_api.md)
+to learn more.

docs/guide/toc.md

@@ -0,0 +1,2 @@
+# [Introduction](introduction.md)
+# [Using the .NET API](using_the_dotnet_api.md)

docs/guide/using_the_dotnet_api.md

@@ -0,0 +1,4 @@
+# Using the SQL Tools Service .NET API
+
+> NOTE: This page will eventually provide usage examples of the .NET
+> API.  For now the [API Reference](../api/index.md) is the best starting point.