Update Videos.markdown

- spelling correction
Merge pull request #277 from ScottSEA/patch-1

Update Videos.markdown
Allowing NuGet Through Firewalls
Removing an unnecessary line break
Update Package-Manager-Console-PowerShell-Reference.markdown
Merge pull request #279 from SetTrend/patch-1

Update-Package: -IgnoreDependencies apparently had wrong description
Update _metadata
Create NuGet-2.8.3.markdown

add NuGet 2.8.3 release notes
Fix wording of last sentence.
Update NuGet-2.8.3.markdown
Update NuGet-2.8.3.markdown
Update NuGet-2.8.3.markdown
Merge pull request #281 from NuGet/nuget-2.5-danliu

Nuget 2.5 danliu
Merge pull request #280 from olivierdagenais/master

Fix wording of last sentence.
refer to Solution Explorer as from Visual Studio

I found these instructions quite confusing. Specifically, I was stumped when I read the instructions which mention Solution Explorer (I eventually discovered it was a screenshot from Visual Studio). I spent an hour looking for the NuGet package that I had installed and from where I should the run the package; I had no idea whether the screenshot had come from a separate NuGet executable or what. Not all readers come from other instructions or pages referencing Visual Studio. I finally found out that that screenshot comes from the Visual Studio Tools menu. Not everyone ends up at the page from a link or some other source that lets us know that once installed, it is accessible from VS. HTH
Merge pull request #282 from muybn/patch-1

refer to Solution Explorer as from Visual Studio
remove extra words in migration script section