Move `validateaddress` from rpcwallet to rpcmisc

Enables it in --disable-wallet compiles.
Delimit wallet-using part using #ifdef ENABLE_WALLET.

Conflicts:
	src/rpcserver.cpp
	src/rpcwallet.cpp
Move `verifymessage` from rpcwallet to rpcmisc

Enables it in --disable-wallet compiles.

Conflicts:
	src/rpcmisc.cpp
	src/rpcserver.cpp
	src/rpcwallet.cpp
Improve logging of failed connections
Refactor: pull alert string sanitization into util
Give peer time-adjustment data an own lock

Instead of relying on cs_main (defined in a different module) to
prevent concurrent access to it.

Conflicts:
	src/main.cpp
	src/util.cpp
Move network-time related functions to timedata.cpp/h

The network time-offset-mangement functions from util.cpp are moved to
timedata.(cpp|h). This breaks the dependency of util on netbase.

Conflicts:
	src/Makefile.am
	src/addrman.h
	src/alert.cpp
	src/qt/transactiondesc.cpp
	src/qt/transactionrecord.cpp
	src/rpcmisc.cpp
	src/rpcnet.cpp
	src/rpcwallet.cpp
	src/util.cpp
	src/util.h
	src/wallet.cpp