Check for redis-cli binary

Signed-off-by: Dmitriy Zaporozhets <dmitriy.zaporozhets@gmail.com>

Signed-off-by: Dmitriy Zaporozhets <dmitriy.zaporozhets@gmail.com>

Signed-off-by: Dmitriy Zaporozhets <dmitriy.zaporozhets@gmail.com>

Signed-off-by: Dmitriy Zaporozhets <dmitriy.zaporozhets@gmail.com>

Signed-off-by: Dmitriy Zaporozhets <dmitriy.zaporozhets@gmail.com>

Execute command directly without using shell

More detailed warning about symlinks in repos_path

   use Shellwords.shellwords for splitting origin_cmd instead of .split(' ')

When that branch contain a '/' in the branch name.
Fix for git over ssh

Fix typos

The syntax for `sed -i` is incompatible between GNU sed and
BSD sed. By Tempfile from the Ruby standard library we can
avoid using the `-i` option of sed.