hide download process and env creation log if not in verbose mode
hide even more log, remove unused statements
hide log for git_accessor
dor print fix
cache apt packages
quite pygame and test_robustus
fix stdout specification in run_shell
review comment fixes, run_shell made to resemble subprocess.call
comment is_self_test
Merge pull request #66 from braincorp/log_refactoring

hide download process and env creation log if not in verbose mode