Merge pull request #2527 from EOSIO/p2p_explicit_req_2475

p2p explicit notify/request feature - issue #2475

libraries/chain/include/eosio/chain/config.hpp

@@ -15,7 +15,7 @@ typedef __uint128_t uint128_t;
 
 const static auto default_block_log_dir     = "block_log";
 const static auto default_shared_memory_dir = "shared_mem";
-const static auto default_shared_memory_size = 1024*1024*1024ll;
+const static auto default_shared_memory_size = 32*1024*1024*1024ll;
 
 const static uint64_t system_account_name    = N(eosio);
 const static uint64_t nobody_account_name    = N(nobody);

plugins/net_plugin/include/eosio/net_plugin/protocol.hpp

@@ -15,7 +15,7 @@ namespace eosio {
    typedef std::chrono::system_clock::duration::rep tstamp;
 
    struct handshake_message {
-      int16_t                    network_version = 0; ///< derived from git commit hash, not sequential
+      uint16_t                   network_version = 0; ///< incremental value above a computed base
       chain_id_type              chain_id; ///< used to identify chain
       fc::sha256                 node_id; ///< used to identify peers and prevent self-connect
       chain::public_key_type     key; ///< authentication key; may be a producer or peer key, or empty