Update version to v1.7.20

Merge pull request #57 from BhargavBhandari90/bbpress-issue

Fix issue of mention for bbpress with bb style pack

Add changelog

Merge pull request #49 from BhargavBhandari90/minor-issue

Minor issue

Merge pull request #48 from BhargavBhandari90/canse-insesnsitve

Canse insesnsitve

Merge pull request #41 from BhargavBhandari90/display-avatar

Add new option for display avatars

Merge pull request #39 from BhargavBhandari90/mention-by-name

Mention by name

Merge pull request #38 from BhargavBhandari90/mention-by-name

Update to v1.7.13

Merge pull request #37 from BhargavBhandari90/mention-by-name

Mention by name

Merge pull request #36 from BhargavBhandari90/mention-by-name

Add filter and script for pro plugin