Merge remote-tracking branch 'hoatle/hot-fix_23_error_when_vagrant_halt_then_up' into develop
add allowed hosts of github, bitbucket to virtual machine [#3]

+ Update README for vm.ssh.forward_agent usage
+ add allowed hosts
Merge remote-tracking branch 'hoatle/enhance_3_add_github_butbucket_to_allowed_hosts_vm' into develop
Fix big problem: ssh does not work on Windows host machine [#23]; this fixes windows password prompt [#30]