Added script and supporting files for creating NuGet package
Modification to NuGet definition: toolkit product name, package details, script updates to handle min max version
Removed max version limit, not necessary with NuGet 2.5
Merge pull request #48 from Esri/hansen/AddNuGetMods

Hansen/add nu get mods
Merge pull request #47 from Esri/zwaap/AddNuGet

Added script and supporting files for creating NuGet package