February 2019 .NET Updates

# February 2019 .NET Updates
The following .NET updates were released in February 2019. This issue will be updated if there are any additional releases during the month.

## .NET Framework
* [.NET Framework February 2019 Security and Quality Rollup - February 12, 2019](https://blogs.msdn.microsoft.com/dotnet/2019/02/13/net-framework-february-2019-security-and-quality-rollup/)
* [.NET Framework February 2019 Preview of Quality Rollup - February 19, 2019](https://blogs.msdn.microsoft.com/dotnet/2019/02/19/net-framework-february-2019-preview-of-quality-rollup/)

## .NET Support Policies
Microsoft support policies are defined in the following documents:

* [Microsoft .NET Support Policy](https://www.microsoft.com/net/support/policy)
* [.NET Core OS Lifecycle Policy](https://github.com/dotnet/core/blob/master/os-lifecycle-policy.md)

The issue body contains the February 2019 release links and support-policy references, but it names no repository file, test, or entry point. Review the listed sources first; the apparent completion condition is adding any further February releases, though the month has already passed and the issue has no current work indicated.

Written by the indexing model from the issue text.