Merge pull request #686

7db89ed ARMv7: fix unaligned accesses (Howard Chu)
5a07cef Wrap some more actions in a larger read txn (Howard Chu)
8cc7a36 read txn/cursor stuff (Howard Chu)
86a7f2b core: check whether an update is needed straight away (moneromooo-monero)
ea5fa5e core: print "update needed" hard fork notifications in red (moneromooo-monero)

src/blockchain_db/berkeleydb/db_bdb.cpp

@@ -1837,7 +1837,7 @@ void BlockchainBDB::set_batch_transactions(bool batch_transactions)
     LOG_PRINT_L3("batch transactions " << (m_batch_transactions ? "enabled" : "disabled"));
 }
 
-void BlockchainBDB::block_txn_start()
+void BlockchainBDB::block_txn_start(bool readonly)
 {
   // TODO
 }