Benchmark gitbase

[ajnavarro]

We need a reproducible way to run a set of queries on a specific subset of repositories, to be able to compare gitbase versions (performance, CPU, memory and so on).

The set of queries is not complete but here is a draft: https://gist.github.com/smola/7013c2ce00788a36d9b57c66521a340d

For the data, we can start using a 10% of the PGA for testing. This 10% should contain always the same siva files.

[erizocosmico]

Currently blocked by #225

[erizocosmico]

Not blocked anymore. #225 addressed in #228