wix: don't show version in title of root feature

The version is already shown in the title bar of the feature selection dialog
and in the text of the welcome dialog. It's unusual for Windows programs to repeat
the version in the root feature.

contrib/wix/mercurial.wxs

@@ -85,7 +85,7 b''
              SourceFile='$(var.VCRedistSrcDir)\policy.x.xx.microsoft.vcxx.crt.x86_msm.msm' />
     </Directory>
 
-    <Feature Id='Complete' Title='Mercurial $(var.Version)' Description='The complete package'
+    <Feature Id='Complete' Title='Mercurial' Description='The complete package'
         Display='expand' Level='1' ConfigurableDirectory='INSTALLDIR' >
       <Feature Id='MainProgram' Title='Program' Description='Mercurial command line app'
              Level='1' Absent='disallow' >