Use latest build tools

Author: joelverhagen

build.ps1

@@ -9,7 +9,7 @@ param (
     [string]$SemanticVersion = '1.0.0-zlocal',
     [string]$Branch,
     [string]$CommitSHA,
-    [string]$BuildBranch = '1c479a7381ebbc0fe1fded765de70d513b8bd68e'
+    [string]$BuildBranch = '802a2329581ab88326bf1fd442595bac6dbaa848'
 )
 
 # For TeamCity - If any issue occurs, this script fail the build. - By default, TeamCity returns an exit code of 0 for all powershell scripts, even if they fail
@@ -69,7 +69,7 @@ Invoke-BuildStep 'Set version metadata in AssemblyInfo.cs' {
 
 Invoke-BuildStep 'Building solution' { 
         $SolutionPath = Join-Path $PSScriptRoot "NuGet.Server.sln"
-        Build-Solution $Configuration $BuildNumber -MSBuildVersion "14" $SolutionPath -SkipRestore:$SkipRestore `
+        Build-Solution $Configuration $BuildNumber -MSBuildVersion "15" $SolutionPath -SkipRestore:$SkipRestore `
     } `
     -ev +BuildErrors