Fixed vsix file include settings
Updated DependsOn version
Merge pull request #46 from Esri/v.next

Merge v10.2.3 into master
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
Change project url to github.com repo
Updated license link, should point to ms-pl license in repo
Added contributing guidelines and link to nuget
Removed slash
Merge branch 'master' of github.com:Esri/arcgis-toolkit-dotnet into dom/vnext_issue35_attribution_grouplayers