change gem to access github with use https:// protocol (port 443) not git:// protocol

git:// protocol used port 9418 and may be blocked by firewalls, but
https port 443 is almost always a good choice.
Merge pull request #256 from nicesw123/https_gem

change gem to access github with https:// protocol (port 443)
Merge branch 'devel' into v0.8-beta