Add netstandard build target for arduino package

Author: glopesdev

Bonsai.Arduino/Bonsai.Arduino.csproj

@@ -2,10 +2,10 @@
 <Project Sdk="Microsoft.NET.Sdk">
   <PropertyGroup>
     <Title>Bonsai - Arduino Library</Title>
-    <Description>Bonsai Arduino Library containing communication infrastructure to probe and control the state of Arduino microcontrollers.</Description>
+    <Description>Bonsai Library containing reactive infrastructure to probe and control the state of Arduino microcontrollers.</Description>
     <PackageTags>Bonsai Rx Arduino</PackageTags>
-    <TargetFramework>net462</TargetFramework>
-    <VersionPrefix>2.6.0</VersionPrefix>
+    <TargetFrameworks>net462;netstandard2.0</TargetFrameworks>
+    <VersionPrefix>2.8.0</VersionPrefix>
   </PropertyGroup>
   <ItemGroup>
     <ProjectReference Include="..\Bonsai.System\Bonsai.System.csproj" />