Add meta info for clients to store custom data in (#113)

* Add meta info for clients to store custom data in

* PR comments

* Really update migration

server/src/main/kotlin/suwayomi/tachidesk/model/table/ChapterMetaTable.kt

@@ -0,0 +1,10 @@
+package suwayomi.tachidesk.model.table
+
+import org.jetbrains.exposed.dao.id.IntIdTable
+import org.jetbrains.exposed.sql.ReferenceOption
+
+object ChapterMetaTable : IntIdTable() {
+    val key = varchar("key", 256)
+    val value = varchar("value", 4096)
+    val ref = reference("chapter_ref", ChapterTable, ReferenceOption.CASCADE)
+}