Api/v1/statuses (#11)

This PR adds:
Statuses

    New status creation.
    View existing status
    Delete a status
    Fave a status
    Unfave a status
    See who's faved a status

Media

    Upload media attachment and store/retrieve it
    Upload custom emoji and store/retrieve it

Fileserver

    Serve files from storage

Testing

    Test models, testrig -- run a GTS test instance and play around with it.

internal/storage/storage.go

@@ -16,9 +16,15 @@
    along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */
 
+// Package storage contains an interface and implementations for storing and retrieving files and attachments.
 package storage
 
+// Storage is an interface for storing and retrieving blobs
+// such as images, videos, and any other attachments/documents
+// that shouldn't be stored in a database.
 type Storage interface {
 	StoreFileAt(path string, data []byte) error
 	RetrieveFileFrom(path string) ([]byte, error)
+	ListKeys() ([]string, error)
+	RemoveFileAt(path string) error
 }