Page styled.

Except for the QoS, Group and Meter tab, all tabs look fancier.

Signed-off-by: Min Chen <minchnew@gmail.com>
Download and upload flows in a batch.

Download all active flows as a file. Copy and paste flows to add many
flows at one time.

Signed-off-by: Lemon Li <lemon.li@pica8.local>
Signed-off-by: Min Chen <minchnew@gmail.com>