Apq/reactive: The Reactive Extensions for .NET @ d3a4e7269557701164ba56bc56a53ceedd6cb6a0

dependabot-preview[bot] 35af1d0301 Bump Verify.Xunit from 8.2.2 to 8.4.0 in /Rx.NET/Source		5 lat temu
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benchmarks	1d19aaff6c Bump .NET Framework minimum version to v4.7.2.	5 lat temu
build	1521fbf7dc Split signing into separate stage (#1055)	6 lat temu
facades	c254324fa7 A few more fixes.	5 lat temu
src	7e6f505c46 Bump System.Linq.Queryable from 4.0.1 to 4.3.0 in /Rx.NET/Source	5 lat temu
tests	35af1d0301 Bump Verify.Xunit from 8.2.2 to 8.4.0 in /Rx.NET/Source	5 lat temu
.gitattributes	a2a03840ac Rename Ix/NET/ to Ix.NET/. Rename Rx/NET/ to Rx.NET/	12 lat temu
.gitignore	9ef67f193f Update approved to include operators	6 lat temu
CodeCoverage.runsettings	ba70227e23 don't run both cc's	6 lat temu
Directory.build.props	7e9e763bb3 Bump Nerdbank.GitVersioning from 3.2.31 to 3.3.37 in /Rx.NET/Source	5 lat temu
Directory.build.targets	3ad1aedaa5 Add nullable attributes for downlevel platforms.	5 lat temu
README.md	c9ef704ffd update readme	8 lat temu
ReactiveX.snk	a2f10c9a1e Change the strong name signing key; check in new one.	9 lat temu
Rx.ruleset	49783c7c67 Remove old Rx.NET sln	9 lat temu
System.Reactive.sln	90052f00a1 Add .NET Core 3 target	7 lat temu
Test.ruleset	746eb76788 Fix errors from xUnit CA	8 lat temu
global.json	393c3019da Use msbuild for sln due to uap	5 lat temu
version.json	08e1e66a2f update ver	5 lat temu

To build all flavors of Rx, you will need Visual Studio 2017 with the UWP and .NET Core workloads installed.