add install_relocation_tools stub

Library/Homebrew/formula_installer.rb

@@ -166,6 +166,7 @@ class FormulaInstaller
 
     if pour_bottle?(:warn => true)
       begin
+        install_relocation_tools if formula.bottle.needs_relocation?
         pour
       rescue => e
         raise if ARGV.homebrew_developer?
@@ -326,6 +327,11 @@ class FormulaInstaller
     @show_header = true unless deps.empty?
   end
 
+  def install_relocation_tools
+    ohai "placeholder"
+    true
+  end
+
   class DependencyInstaller < FormulaInstaller
     def initialize(*)
       super