add ability to change namespace from project edit page

app/models/ability.rb

@@ -7,6 +7,7 @@ class Ability
       when "Note" then note_abilities(object, subject)
       when "Snippet" then snippet_abilities(object, subject)
       when "MergeRequest" then merge_request_abilities(object, subject)
+      when "Group" then group_abilities(object, subject)
       else []
       end
     end
@@ -61,6 +62,16 @@ class Ability
       rules.flatten
     end
 
+    def group_abilities user, group
+      rules = []
+
+      rules << [
+        :manage_group
+      ] if group.owner == user
+
+      rules.flatten
+    end
+
     [:issue, :note, :snippet, :merge_request].each do |name|
       define_method "#{name}_abilities" do |user, subject|
         if subject.author == user

app/models/project.rb

@@ -84,6 +84,16 @@ class Project < ActiveRecord::Base
       where("projects.name LIKE :query OR projects.path LIKE :query", query: "%#{query}%")
     end
 
+    def find_with_namespace(id)
+      if id.include?("/")
+        id = id.split("/")
+        namespace_id = Namespace.find_by_path(id.first).id
+        where(namespace_id: namespace_id).find_by_path(id.last)
+      else
+        find_by_path(id)
+      end
+    end
+
     def create_by_user(params, user)
       namespace_id = params.delete(:namespace_id)
       namespace_id ||= user.namespace.try(:id)