Database updates (#144)

* start moving some database stuff around

* continue moving db stuff around

* more fiddling

* more updates

* and some more

* and yet more

* i broke SOMETHING but what, it's a mystery

* tidy up

* vendor ttlcache

* use ttlcache

* fix up some tests

* rename some stuff

* little reminder

* some more updates

internal/db/media.go

@@ -0,0 +1,27 @@
+/*
+   GoToSocial
+   Copyright (C) 2021 GoToSocial Authors admin@gotosocial.org
+
+   This program is free software: you can redistribute it and/or modify
+   it under the terms of the GNU Affero General Public License as published by
+   the Free Software Foundation, either version 3 of the License, or
+   (at your option) any later version.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU Affero General Public License for more details.
+
+   You should have received a copy of the GNU Affero General Public License
+   along with this program.  If not, see <http://www.gnu.org/licenses/>.
+*/
+
+package db
+
+import "github.com/superseriousbusiness/gotosocial/internal/gtsmodel"
+
+// Media contains functions related to creating/getting/removing media attachments.
+type Media interface {
+	// GetAttachmentByID gets a single attachment by its ID
+	GetAttachmentByID(id string) (*gtsmodel.MediaAttachment, Error)
+}