Fix typo in previous commit
Mix the paste ID into paste sha
Paste deletion webhook
Flush database during paste creation
Implemented paste deletion in API
Extract paste file addition to a helper function
Implement paste deletion

Added locks for blob creation/deletion

Fixes #13
Fix logic in paste user page
Set a max width for images
/pastes: redirect to /~<current_user>
Paste views: link to user index
Display visibility for pastes
Added an API endpoint to get a user's pastes
Add pagination to /pastes
Add /~<user> view

Fixes #17
Set default paste visibility to unlisted on API
Updates per centered design
Don't access contents before it's validated
Update to Alpine 3.10
.builds/alpine.yml: update repo path