add bps limiter (#1015)

* add token bucket
* remove quinn-proto

easytier/src/proto/common.proto

@@ -40,6 +40,9 @@ message FlagsInConfig {
   bool enable_quic_proxy = 24;
   // does this peer allow quic input
   bool disable_quic_input = 25;
+
+  // a global relay limit, only work for foreign network
+  uint64 foreign_relay_bps_limit = 26;
 }
 
 message RpcDescriptor {
@@ -180,3 +183,9 @@ message PortForwardConfigPb {
 message ProxyDstInfo {
   SocketAddr dst_addr = 1;
 }
+
+message LimiterConfig {
+  optional uint64 burst_rate = 1; // default 1 means no burst (capacity is same with bps)
+  optional uint64 bps = 2; // default 0 means no limit (unit is B/s)
+  optional uint64 fill_duration_ms = 3; // default 10ms, the period to fill the bucket
+}