Link tool: 'Add link' and misc UI improvements

Change-Id: I1a805fee04e2e005987827179434e6b30a17a52b
Avoid reference links from triggers for link cards

Change-Id: I62f4fe180023cb11f4956882a0d263b0cd66920b
Merge "Link tool: 'Add link' and misc UI improvements"
Merge "Avoid reference links from triggers for link cards"