Fix missing Add Category button in PW 2.4. Add buttons for deleting categories. Fix lots of php notices. Update Flourish libraries.
Fix issues with blank vs NULL for port. Added force secure option. Fix for plain text vs HTML emails.
Merge pull request #1 from adrianbj/master

Fix missing Add Category button in PW 2.4. Add buttons for deleting categories. Fix lots of php notices. Update Flourish libraries.