1) update master inteface of datanode enable qos
2) master clean client info if long time no report
3) enable qos online shutdown and startup
4) master set client alloc preriod and count of girds hit trigger condition
5) datanode qos limit value set by master and add disable conf and http interface
6) client qos init buffer calculate according on real buffer storage
7) create limiter for both hot and cold volume
Signed-off-by: leonrayang <chl696@sina.com>
