WIP: Allow attachments for comments
WIP: Allow attachments for issues, not only comments
Add delete route for attachments, remove upload buttons from issues/comments
Merge branch 'dev' into feature/attachments

Conflicts:
	models/issue.go
	routers/repo/issue.go
Fix missing . (dot) in issue templates
Allow admins to delete attachments.
Add files/ directory to .gitignore
Show attachments in issues/comments and add preview for images
Add file upload for attachments
Update default config with comments
Allow disabling uploads
Change Attachment.Path to TEXT (no maximum size)
Merge pull request #307 from nuss-justin/feature/attachments

Feature: Ability to attach files to issues (attachments)