Restrict env variables passed to git-xxx-pack
Use built-in Ruby Dir.pwd instead of the shell
Use IO.popen instead of Kernel#` to read refs
Use less shell commands in gitlab_projects_spec.rb
Use safer shell invocations in bin/install
 Merge branch 'shell_style' into 'master'

Shell Style
 Merge branch 'environment_variables' into 'master'

Restrict Environment Variables
Version 1.8.1

Signed-off-by: Dmitriy Zaporozhets <dmitriy.zaporozhets@gmail.com>
Merge remote-tracking branch 'upstream/master'