Update locate-vs.ps1 to write out failure information

Update nuspec

Remove the depedency projects

Update locate-vs.ps1 to write out any exceptions it may encounter so that we can start to diagnose failures in pull request builds.

Add sync path for loading text

The dependency projects were added as a way to help unify our project.json references.  Instead of every project referencing the NuGet package, we had a dependency project which referenced it and everyone referenced that dependency project.  Due to the transitive nature of NuGet it would be roughly equivalent.

This system had a number of downsides:

1. There was no enforcement.  Even though dependency projects existed, there was no mechanism to force developers to use them.
2. Getting the granularity correct was tricky.
3. The projects themselves have special props / targets to get them to produce no output.  This can trip up MSBuild up to date checks.

Since then though we've begun using RepoUtil to verify our NuGet reference correctness.  This removed the need for these projects and hence I'm removing them from our build.

Merge dev15-rc2 into master

Create a custom Rename-File code operation so that we don't show a very unhelpful 'full file added' preview.

Preserve modifiers when extracting out a nested type.

Always make suggestion tags two characters.

Merge dev15-rc2 into master

Don't crash if we can't resolve a file during a TempPE build

Create a custom Rename-File code operation so that we don't show a very unhelpful 'full file added' preview.

Do not offer 'inline declaration' if it would break scoping.

Fix fallback encoding case; canBeEmbedded was not propogated

Extend RepoUtil so it can support our internal repo

added a test for https://github.com/dotnet/roslyn/issues/14878

Since this involves the filesystem, there's always the possibility
the file might disappear out from underneath you. Let's accept that
might happen.

Fixes dotnet/roslyn#15101.

Our internal repo uses dotnet/roslyn as a submodule.  It has additional project.json entries that need to go through the same verification as dotnet/roslyn.  This updates RepoUtil so it can handle this structure.  In particular having the configuration file and generation files be in non-standard locations.

Account for bad commit missing

Make the GoToDefinitionHelper sit on top of the new FindUsages presenter

Move helpers to common layer.