Improve UI

Signed-off-by: Takashiro <takashiro@qq.com>
Fix a notice

Signed-off-by: Takashiro <takashiro@qq.com>
Add copyright and runtime infomation

Signed-off-by: Takashiro <takashiro@qq.com>
Reduce SQL queries of market.php

Signed-off-by: Takashiro <takashiro@qq.com>
Cache active announcements

Signed-off-by: Takashiro <takashiro@qq.com>
Fix a typo

Signed-off-by: Takashiro <takashiro@qq.com>
Remove a useless parameter from Mysql::fetch_all()

Signed-off-by: Takashiro <takashiro@qq.com>
Fix a bug that Product::FetchFilteredPrices dies on handling empty products

Signed-off-by: Takashiro <takashiro@qq.com>