Update README.md

Fixed links.
issue #33: added django-social-auth to requirements and made required changes in emergent/settings.py and emergent/urls.py
issue #33: created login page with info about GitHub as only way to login
Merge remote-tracking branch 'remotes/upstream/master' into issue-33-github-login
issue #33: removed registration and all mentions of registration.
issue #45: implemented including local settings if file emergent/local_settings.py exists
issue #45: PEP8. Removed trailing whitespace from the settings file.
Merge pull request #46 from trilliput/master

issue #45: implemented including local settings
Merge remote-tracking branch 'upstream/master' into issue-33-github-login

Conflicts:
	emergent/settings.py
Merge remote-tracking branch 'remotes/upstream/rpg_ui' into issue-33-github-login

Conflicts:
	emergent/urls.py
Merge pull request #47 from trilliput/issue-33-github-login

fix #33 github login