Add a simple spec

Spec.md

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+Event log based store
+
+The data rows of our table are to be recreated from an event log
+All interactions with the rows is to happen exclusively via events from/in the log
+For performance reasons we are to cache these data rows as well for quick lookup
+
+Events in the log are to take form of:
+type Event struct {
+	Seq int
+	Type "create"|"update"|"delete"
+	Hash string
+	ItemID string // uuid-v4
+	EventID string // uuid-v4
+	Data map[string]interface{}
+	Timestamp datetime
+}
+Events are divided into 3 types, create update and delete events
+Create events simply create the object as given in Data
+Delete events simply mark an object as deleted (not actually delete!) via its ItemID
+Update events are to modify a field of a row and never more than one field
+Therefore its data is only the diff in the form of "age = 3"
+
+When creating an event only the Type and ItemID must be provided
+Data is optional (delete events have no data)
+Hash, EventID and Seq are to be computed server side
+
+On the server side with an incoming event:
+Grab the latest event
+Assign the event a sequence number that is incremented from the latest
+Create its EventID (generate a uuid-v4)
+Assign it a Timestamp
+Compute the hash from the dump of the current event PLUS the previous event's hash
+And only then apply the patch
+For create events that is insert objects
+For delete events that is mark objects as deleted
+For update events get the object, apply the diff and sav the object