windows: the installer depends on the data (voice, language) files

src/windows/espeak-ng.sln

@@ -1,7 +1,7 @@
 
 Microsoft Visual Studio Solution File, Format Version 12.00
-# Visual Studio 14
-VisualStudioVersion = 14.0.24720.0
+# Visual Studio 15
+VisualStudioVersion = 15.0.26430.12
 MinimumVisualStudioVersion = 10.0.40219.1
 Project("{8BC9CEB8-8B4A-11D0-8D11-00A0C91BC942}") = "libespeak-ng", "libespeak-ng.vcxproj", "{A47A0CFD-FE52-40B4-8CEC-EE1BD4282CDD}"
 EndProject
@@ -13,6 +13,9 @@ Project("{8BC9CEB8-8B4A-11D0-8D11-00A0C91BC942}") = "data", "data.vcxproj", "{8C
 	EndProjectSection
 EndProject
 Project("{930C7802-8A8C-48F9-8165-68863BCCD9DD}") = "installer", "installer\installer.wixproj", "{B67CE3B2-D1D7-45B9-98DA-164E3837D7BC}"
+	ProjectSection(ProjectDependencies) = postProject
+		{8C406BE8-2F85-426B-8009-A2DD540DF7CD} = {8C406BE8-2F85-426B-8009-A2DD540DF7CD}
+	EndProjectSection
 EndProject
 Global
 	GlobalSection(SolutionConfigurationPlatforms) = preSolution