remove minimum-stability
fix #51 (error while getting list of references)
tests fix
process timeouts and some refactoring
bug #52 tests fix (seva-ask)

This PR was merged into the master branch.

Discussion
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tests fix

Hello!
I have found that some tests are broken because of typos, so I have fixed them.

Commits
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43a1191 tests fix
Merge pull request #53 from seva-ask/processTimeouts

process timeouts and some refactoring
empty reference bag error
symfony/process version fixed to 2.4.*

* fixes #54
changed symfony/process version name to tild pattern
Merge pull request #55 from pitpit/bugfix-54

symfony/process version fixed to 2.4.*
rough support of submodules
missed a class
refactor the Commit plumbery
git log loads data in commit
do not fetch all commit hashes, only the count
Merge pull request #57 from gitonomy/refactoring-perf

Refactoring perf
added Gitonomy\Git\Admin::cloneBranchTo to clone a repository and point head to a specific branch
Merge pull request #58 from pitpit/feature-cloneBranchTo

Add ability to clone a repository and point head to a specific branch in one call
verify Commit::getTree - #59
Merge pull request #1 from gitonomy/master

update master