boost::replace_all needs an additional include

boost::replace_all in wallet.cpp needs an additional include.

located here: https://github.com/earthcoinproject/earthcoin/blob/master/src/wallet.cpp#L403
and introduced in this commit: https://github.com/earthcoinproject/earthcoin/commit/243ac4b2a9fc92ae36386a1ac86727eddab40950#diff-d7618bdc04db23aa74d6a5a4198c58fdR403