Add global.IsAdmin

Quickly check to see logged in user is an admin.
Merge pull request #459 from enkodellc/master

Add global.IsAdmin
Fix for UserSchema definition roles attribute - String -> Array
Merge pull request #463 from dragulceo/fix_user_schema_roles

Fix for UserSchema definition roles attribute - String -> Array
Fallback to facebook email if username is undefined
Missing page-header closing Div
Merge pull request #464 from enkodellc/master

Missing page-header closing Div
Use 'jack' instead of 'jack@aol.com' for Facebook username
Merge pull request #466 from jackcarter/master

Fallback to first part of facebook email if username is undefined
#470 user.roles.length
show how to install grunt-cli
Merge remote-tracking branch 'upstream/master'

Conflicts:
	public/system/views/header.html