Add mentions' SQL definitions

Signed-off-by: Shitiz Garg <mail@dragooon.net>
Add ability to mention others in posts via @username

Signed-off-by: Shitiz Garg <mail@dragooon.net>
Add [member] BBC

Signed-off-by: Shitiz Garg <mail@dragooon.net>
Add active suggestions while mentioning in a post

Signed-off-by: Shitiz Garg <mail@dragooon.net>
Fix a little JS error on topic display

Signed-off-by: Shitiz Garg <mail@dragooon.net>
Implement a separate admin area for mentions

Signed-off-by: Shitiz Garg <mail@dragooon.net>
Missed an Admin mention setting

Signed-off-by: Shitiz Garg <mail@dragooon.net>
Merge pull request #1722 from Dragooon/mentions

Mentions