v2.0.0-preview.6

This prerelase update includes the following updates:

• Added reload method to mgt-agenda - #754 (thanks @sebastienlevert)
• Added global config to disable Contact Apis in mgt-person - #753
• Added support for transitive search when group-id is set on mgt-people-picker - #741 (thanks @sebastienlevert)
• Updated mgt-people-picker to use new advanced user search api - #742
• Updated mgt-people-picker to search group members via Graph calls instead of fetching all members first - #741 (thanks @sebastienlevert)
• Fixed mgt-people-picker input box deleting characters - #765