Revert "fix unmarshalling request error"

This reverts commit 35be548.

Depending on whetther the document has pages, koreader sends payload with the following formats.

{"percentage":0.005,"device":"device_name","device_id":"B78EA04ACC3A453DBA220D720C0BE102","document":"348e34463a44ba68659fc6fe814a6778","progress":3}

{"percentage":1,"device":"device_name","device_id":"B78EA04ACC3A453DBA220D720C0BE102","document":"4eb484b229696cb39cd8fe5495aa1bbe","progress":"\/body\/DocFragment[30]\/body\/p\/img.0"}

We can not blindly unmarshal progress into int or string.

handledb.go

@@ -40,7 +40,7 @@ type dbDocument struct {
 	Username   string  `db:"username"`
 	DocumentID string  `db:"documentid"`
 	Percentage float64 `db:"percentage"`
-	Progress   int64   `db:"progress"`
+	Progress   string  `db:"progress"`
 	Device     string  `db:"device"`
 	DeviceID   string  `db:"device_id"`
 	Timestamp  int64   `db:"timestamp"`

kosyncsrv.go

@@ -22,7 +22,7 @@ type requestHeader struct {
 type requestPosition struct {
 	DocumentID string  `json:"document"`
 	Percentage float64 `json:"percentage"`
-	Progress   int64   `json:"progress"`
+	Progress   string  `json:"progress"`
 	Device     string  `json:"device"`
 	DeviceID   string  `json:"device_id"`
 }