More SQLite (#871)

* SQLite support for appservice

* SQLite support for mediaapi

* Copyright notices

* SQLite for public rooms API (although with some slight differences in behaviour)

* Lazy match aliases, add TODOs

mediaapi/storage/sqlite3/sql.go

@@ -0,0 +1,36 @@
+// Copyright 2017-2018 New Vector Ltd
+// Copyright 2019-2020 The Matrix.org Foundation C.I.C.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package sqlite3
+
+import (
+	"database/sql"
+)
+
+type statements struct {
+	media     mediaStatements
+	thumbnail thumbnailStatements
+}
+
+func (s *statements) prepare(db *sql.DB) (err error) {
+	if err = s.media.prepare(db); err != nil {
+		return
+	}
+	if err = s.thumbnail.prepare(db); err != nil {
+		return
+	}
+
+	return
+}