Add search box for the commit.

app/controllers/graph_controller.rb

@@ -7,6 +7,16 @@ class GraphController < ProjectResourceController
   before_filter :require_non_empty_project
 
   def show
+    if params.has_key?(:q) && params[:q].blank?
+      redirect_to project_graph_path(@project, params[:id])
+      return
+    end
+
+    if params.has_key?(:q)
+      @q = params[:q]
+      @commit = @project.repository.commit(@q) || @commit
+    end
+
     respond_to do |format|
       format.html
       format.json do