Improve logging around connection establishment

[lutovich]

It will help diagnose long running TLS handshakes.

Example log:

2017-09-26 06:58:47,115 [Connection] [1206883981] Connecting to localhost:7687, secure: true
2017-09-26 06:58:47,117 [Connection] [1206883981] Running TLS handshake
2017-09-26 06:58:47,139 [Connection] [1206883981] TLS handshake completed
2017-09-26 06:58:47,139 [Connection] [1206883981] Connected to localhost:7687, secure: true
2017-09-26 06:58:47,139 [Connection] [1206883981] Negotiating protocol with localhost:7687
2017-09-26 06:58:47,139 [Connection] [1206883981] C: [HANDSHAKE] 0x6060B017
2017-09-26 06:58:47,140 [Connection] [1206883981] C: [HANDSHAKE] [1, 0, 0, 0]
2017-09-26 06:58:47,141 [Connection] [1206883981] S: [HANDSHAKE] -> 1
2017-09-26 06:58:47,142 [Connection] [1206883981] Selected protocol class org.neo4j.driver.internal.net.SocketProtocolV1 with localhost:7687

which gives us timestamps for various connection establishment stages.