Add more storage statistics

This adds counters for build artifacts and LFS objects, and moves
the preexisting repository_size and commit_count from the projects
table into a new project_statistics table.

The counters are displayed in the administration area for projects
and groups, and also available through the API for admins (on */all)
and normal users (on */owned)

The statistics are updated through ProjectCacheWorker, which can now
do more granular updates with the new :statistics argument.

1 files changed, 6 insertions, 0 deletions

diff --git a/spec/factories/project_statistics.rb b/spec/factories/project_statistics.rb
new file mode 100644
index 00000000000..72d43096216
--- /dev/null
+++ b/spec/factories/project_statistics.rb
@@ -0,0 +1,6 @@
+FactoryGirl.define do
+  factory :project_statistics do
+    project { create :project }
+    namespace { project.namespace }
+  end
+end