Change tool version in CLUCoreCLR.sln to avoid merge conflict

Author: johanste

src/CLU/CLUCoreCLR.sln

@@ -1,7 +1,7 @@
 
 Microsoft Visual Studio Solution File, Format Version 12.00
 # Visual Studio 14
-VisualStudioVersion = 14.0.24720.0
+VisualStudioVersion = 14.0.23107.0
 MinimumVisualStudioVersion = 10.0.40219.1
 Project("{8BB2217D-0F2D-49D1-97BC-3654ED321F3B}") = "Commands.Common", "Commands.Common\Commands.Common.xproj", "{5F567ACA-595E-436D-83DB-A21E08F82DF6}"
 EndProject