Merge branch 'release/v2.8'
Merge branch 'release/v2.8.1'
Merge branch 'release/v2.8.2'
Merge branch 'release/v2.8.3'
Merge branch 'release/v2.8.4'
Merge branch 'release/v2.8.4'
Merge branch 'release/v2.8.5'
making notification base type class an abstract class
Merge pull request #328 from BFTrick/notification-abstract

Make Notification Base Type Class an Abstract Class
Revert "Make Notification Base Type Class an Abstract Class"
Merge pull request #350 from wpninjas/revert-328-notification-abstract

Revert "Make Notification Base Type Class an Abstract Class"
Update readme.txt
Merge branch 'release/v2.8.6'
Merge branch 'release/v2.8.7'
Removing un-necessary settings files.
Fixed several strings that weren't internationalised properly.
Removed HubSpot from the add-ons list.
Removing unnecessary functions.
Removed the Form Settings help tab until new information can be added.
Code cleanup.