Infer proper types within tuples.

Adjust cases where we offer ?.Invoke

* Add dotnet-tools feed

* Update PDB Converter to 1.1.0-beta2-20115-01

* Remove symreader-converter myget feed

* Add dotnet5 feed

* Remove symreader, symreader-portable, sourcelink myget feeds

- Microsoft.DotNet.Arcade.Sdk - 5.0.0-beta.20151.1

Add test to demonstrate proper behavior.

Add test to validate proper intellisense.

Update src/Workspaces/SharedUtilitiesAndExtensions/Workspace/CSharp/LanguageServices/CSharpTypeInferenceService.TypeInferrer.cs
Co-Authored-By: NSam Harwell <sam@tunnelvisionlabs.com>

Filter out duplicate items in attribute sig help.

Do not show is/as/switch after method/lambdas

Add test to validate scenario.

Fixup paths in our shared libraries.

Do not qualify local functions whne complexifying them.

Add test demonstrating proper behavior.

Add test demonstrating feature works properly

Merge release/dev16.6-preview1 to master

Update GetOption to return the default option value

Make it simple to generate auto-properties from the SyntaxGenerator API.

Merge release/dev16.5 to release/dev16.6-preview1

- Microsoft.DotNet.Arcade.Sdk - 5.0.0-beta.20129.1

Switch more code from ISyntaxFactsService to ISyntaxFacts

* Add overload used by Razor via IVT back

* Update src/Workspaces/Core/Portable/Workspace/Solution/DocumentInfo.cs
Co-Authored-By: NJason Malinowski <jason.malinowski@microsoft.com>
Co-authored-by: NJason Malinowski <jason@jason-m.com>

Follow up to https://github.com/dotnet/roslyn/pull/42015/files#r385741503
This change allows couple of things:
1. Make C# and VB ISyntaxFactsService implementation private nested types.
2. Aid future porting of analyzers to CodeStyle layer by moving bunch of our analyzers/fixers/helpers to use ISyntaxFacts as opposed to ISyntaxFactsService, latter is not available in CodeStyle analyzer layer.

- Microsoft.DotNet.Arcade.Sdk - 5.0.0-beta.20128.3