Integrated changes to build mechanism.

Build functionality was moved to the Visual Studio package; this has been integrated into the rest of the project. Project was also updated to the latest Visual Studio version/SDK.
Migrated NuGet.
Fixed issue with package manifest.
Updated all NuGet packages.
Don't enable project support by default.
Fixed incorrect check for missing extension.
Run NuGet query inside try/catch.
Merge remote-tracking branch 'other/master'

Conflicts:
  Build/Support/Build.ps1
  NetIde.Core/BuildConfig.xml
  NetIde.Core/NetIde.Core.csproj
  NetIde.Core/PackageManagement/PackageManagementForm.cs
  NetIde.Core/Resources/NiMenu.Generated.xml
  NetIde.Core/Resources/NiMenu.xml
  NetIde.Core/packages.config
  NetIde.Shell/NetIde.Shell.csproj
  NetIde.Shell/packages.config
  NetIde.VisualStudio/source.extension.vsixmanifest
  NetIde.sln
  NetIde/NetIde.csproj
  NetIde/packages.config
  Support/Schemas
Fixed Visual Studio package manifest.

The package manifest for the Visual Studio plugin had a dependency to NuGet. This doesn't work for recent versions of Visual Studio. Removed the dependency and support for older Visual Studios.