Update readme-qt.rst

Otherwise the compilation exits with the error because miniupnpc is required
but not installed.
add OpenSSL RAND_cleanup() on OpenSSL shutdown

- to securely erase the memory used by the PNRG
- also rework 2 comments in OpenSSL init
Add GetTimeMicros() for ore accurate benchmarking

Conflicts:
	src/util.h
Added ping time measurement.
New RPC "ping" command to request ping.
Implemented "pong" message handler.
New "pingtime" field in getpeerinfo, to provide results to user.
New "pingwait" field, to show pings still in flight, to better see newly lagging peers.

Conflicts:
	src/bitcoinrpc.cpp
	src/bitcoinrpc.h
	src/main.cpp
	src/net.cpp
	src/net.h
	src/rpcnet.cpp
Ping automatically every 2 minutes (unconditionally)

... instead of after 30 minutes of no sending, for latency measurement
and keep-alive. Also, disconnect if no reply arrives within 20 minutes,
instead of 90 of inactivity (for peers supporting the 'pong' message).

Conflicts:
	src/net.cpp
	src/net.h
Use pong receive time rather than processing time

Conflicts:
	src/main.cpp
remove maarx.blackcoin.co seed

it is offline for time being
add new dns seed
Break up CAddrMan's IMPLEMENT_SERIALIZE
walletpassphrase: check timeout value
Silence useless warning in src/json/json_spirit_writer_template.h to make important warnings easier to see.

warning: typedef ‘Char_type’ locally defined but not used [-Wunused-local-typedefs]
Remove enforcecanonical option, it's always active from now.

Conflicts:
	src/init.cpp
	src/main.cpp
Add redeemScript to listunspent output and signrawtransaction input

signrawtransaction was unable to sign pay-to-script-hash inputs
when given the list of private keys to use. With this commit
you can provide the p2sh redemption script in the list of
inputs.

Conflicts:
	src/rpcrawtransaction.cpp
	src/test/rpc_tests.cpp
Signrawtransaction shouldn't require redeemScript for non-p2sh txins.

The redeemScript functionality broke plain offline signing, this
change makes it only look for that parameter when signing a p2sh
input.
refactor locking of CTxMemPool::addUnchecked()
Moved SyncWithWallets out of ProcessMessage and into CTxMemPool::accept() so that when adding multiple wallets they will be aware of each other's transactions.

Conflicts:
	src/main.cpp
Remove dead transaction replacement code

This dead code can be resurrected from git history if
transaction replacement is ever implemented. Keeping
dead code in the source is a bad idea, because it implies
it was tested and worked at some point, which is not true.

Conflicts:
	src/main.cpp
remove CTransaction::IsNewerThan which is never used
Add missing FindNode prototype to net.h

Also make the argument a const std::string & instead of pass-by-value.
Add comment about never updating nTimeOffset past 199 samples

Refer to issue #4521 for details.

Conflicts:
	src/timedata.cpp