Merge branch 'maintenance/1.7' into experimental

# Conflicts:
#	.gitignore
#	R.NET/RDotNet.csproj
#	RDotNet.FSharp.Tests/RDotNet.FSharp.Tests.fsproj
#	RDotNet.FSharp/RDotNet.FSharp.fsproj
#	RDotNet.Graphics.Tests/RDotNet.Graphics.Tests.csproj
#	RDotNet.Graphics/RDotNet.Graphics.csproj
#	RDotNet.NativeLibrary/RDotNet.NativeLibrary.csproj
#	RDotNet.TestBase/RDotNet.TestBase.csproj
#	RDotNet.Tests.sln
#	RDotNet.Tests/RDotNet.Tests.csproj
#	README.md
#	TestApps/EngineDisposeTest/EngineDisposeTest.csproj
#	TestApps/MeasureRuntime/MeasureRuntime.csproj
#	TestApps/RDotNet.SetEnv.Tests.32/RDotNet.SetEnv.Tests.32.csproj
#	TestApps/RDotNet.SetEnv.Tests.64/RDotNet.SetEnv.Tests.64.csproj
#	TestApps/RDotNet.SetEnv.Tests/RDotNet.SetEnv.Tests.csproj
#	TestApps/SimpleTest/SimpleTest.csproj
#	TestApps/StressTest/StressTest.csproj