add appveyor.yml

Author: phnx47

README.md

@@ -1,5 +1,7 @@
 # Prometheus .NET Client
 
+[![Build status](https://ci.appveyor.com/api/projects/status/ik6p8hv9he1cl0a9?svg=true)](https://ci.appveyor.com/project/phnx47/prometheus-client) [![License MIT](https://img.shields.io/badge/license-MIT-green.svg)](https://opensource.org/licenses/MIT) [![NuGet Badge](https://buildstats.info/nuget/Prometheus.Client)](https://www.nuget.org/packages/Prometheus.Client/) 
+
 This is an experimental dot net core version (unofficial).
 
 Its a fork of [prometheus-net](https://github.com/andrasm/prometheus-net)

appveyor.yml

@@ -0,0 +1,16 @@
+version: '{build}-{branch}'
+image: Visual Studio 2017
+clone_folder: c:\projects\prometheus.client
+build_script:
+- cmd: dotnet restore src\Prometheus.Client && dotnet pack src\Prometheus.Client -c Release --include-symbols
+test_script:
+- cmd: dotnet restore test\Prometheus.Client.Tests && dotnet test test\Prometheus.Client.Tests\Prometheus.Client.Tests.csproj
+artifacts:
+- path: '**\*.nupkg'
+  name: All Nupkg
+deploy:
+- provider: NuGet
+  api_key:
+    secure: vukCl5k+S4fJtqeYNiB9ufy/NUCw+60cPcqnPoqvykBjSo8Ub8QtEfZNN9qvj5Jh
+  on:
+    appveyor_repo_tag: true