mookjp/pool — pull request #79 by mookjp (2014-12-04 16:04:01+00:00)
Title: [WIP] Change to fetch everytime

For now, Builder does not fetch origin after the repository was cloned at first time.
This change does `fetch` command before `rev-parse` so that if branch name was given, pool can return the latest commit related to branch name everytime.