Make some adaptations for AppVeyor to pass (#111)

Author: jaenyph

appveyor.yml

@@ -0,0 +1,21 @@
+image: Visual Studio 2017
+
+services:
+  - mssql2014
+  
+build_script:
+  - build.cmd
+  
+before_build:
+  - dotnet restore
+  
+test_script:
+  - test.cmd
+  
+# replace the db connection with the local instance :
+before_test:
+- ps: >-
+    $config = join-path (Resolve-Path .\).Path '.\src\DelegateDecompiler.EntityFramework.Tests\App.config';
+    $doc = (gc $config) -as [xml]; 
+    $doc.SelectSingleNode('//connectionStrings/add[@name="DelegateDecompilerEfTestDb"]').connectionString = "Server=(local)\\SQL2014;Database=DelegateDecompilerEfTestDb;MultipleActiveResultSets=True;User ID=sa;Password=Password12!"; 
+    $doc.Save($config);

build.bat

@@ -0,0 +1 @@
+dotnet msbuild DelegateDecompiler.sln /p:Configuration=Release

build.cmd

@@ -0,0 +1,5 @@
+nunit3-console ^
+ src\DelegateDecompiler.Tests\bin\Release\net40\DelegateDecompiler.Tests.dll ^
+ src\DelegateDecompiler.Tests.VB\bin\Release\net40\DelegateDecompiler.Tests.VB.dll ^
+ src\DelegateDecompiler.EntityFramework.Tests\bin\Release\net45\DelegateDecompiler.EntityFramework.Tests.dll ^
+ --result=DelegateDecompiler.testsresults.xml;format=AppVeyor