def blob_at(revision, path)
      tree = Rugged::Commit.lookup(self, revision).tree
      begin
        blob_data = tree.path(path)
      rescue Rugged::TreeError
        return nil
      end
      blob = Rugged::Blob.lookup(self, blob_data[:oid])
      (blob.type == :blob) ? blob : nil
    end
def blob_at(revision, path)
      tree = Rugged::Commit.lookup(self, revision).tree
      begin
        blob_data = tree.path(path)
      rescue Rugged::TreeError
        return nil
      end
      blob = Rugged::Blob.lookup(self, blob_data[:oid])
      (blob.type == :blob) ? blob : nil
    end
Get the blob at a path for a specific revision.

 revision - The String SHA1.
 path     - The String file path.

 Returns a Rugged::Blob object