Restore projects on build

This changes MSBuild to restore packages on build, to avoid immediately getting
building about missing assets files the first time you clone the repository. This
added 1.8 seconds to build time on my i7-9700k if restore is up-to-date.

build.cmd

@@ -3,7 +3,7 @@
 @echo.This script simply calls msbuild to build PerfView.exe
 @echo.*************************************************************
 @echo.
-msbuild /p:Configuration=Release %*
+msbuild /restore /p:Configuration=Release %*
 @if '%ERRORLEVEL%' == '0' (
     echo.
     echo.