Combine with .nuspec file if found at root of the project

[mayerwin]

First, thank you so much for publishing this plugin! It is exactly what I was looking for. Simple and efficient.

It would really deserve to be highlighted in NuGet's official doc as an option to help beginners get started with packaging and publishing NuGet packages without the need to use the command line. It would make it easier to find NuGet.Packer (I found it almost by accident by browsing through the many NuGet packages containing "NuGet").

Two things that would be nice:

1. If not already supported, combining with data found in a .nuspec file, if found at the root of the project (apparently nuget should support it out of the box: http://stackoverflow.com/questions/14797525/differences-between-nuget-packing-a-csproj-vs-nuspec)
2. Publishing a Visual Studio extension that would piggyback on NuGet.Packer (if found present in project files), to provide the functionality of manually generating/publishing the package file with a contextual menu item on the project ("Generate NuGet package", "Generate and publish NuGet package", the latter only if the appropriate publishing credentials are available). And if supported by Visual Studio extensibility framework, expose the NuGet.Packer configuration options as a new tab in the project window (easier to modify than editing the csproj file directly).

As a reference, Create New NuGet Package From Project After Each Build is one other extension that seems to be trying to achieve the same results, though I prefer the more invisible (but not less configurable) approach of NuGet.Packer.