Replace TConnection with TClientImpl in JDBC

[nicktorwald]

Replace obsolete TarantoolConnection with TarantoolClient to have an
ability to perform async operations.

Update SQLDriver URL parameters. Add init and operation timeouts.
Remove socket timeout and replace socket provider with socket channel
provider options (according to TarantoolConnection-to-TarantoolClient
transfer written above).

Add operation timeout capability to TarantoolClientImpl. It also affects
the cluster client which no more needs its own expirable operations.

Add base support for SQLStatement (setQueryTimeout) to execute requests
with timeout using new TarantoolClient operation timeout.

Remove deprecated JDBCBridge. SQLConnection accepted the responsibility
for producing raw SQL results.

Update README doc with respect to JDBC driver options changes.

Closes: #163
Follows on: #75, #155

[coveralls]

Coverage increased (+0.6%) to 70.422% when pulling 0328ca9 on nicktorwald/gh-163-remove-tnt-connection into 1cafd58 on master.

[Totktonada]

Maybe we misunderstood each other. I would leave TarantoolConnection itself for compatibility (say, YSCB use it), but use TarantoolClientImpl in JDBC part of the connector.

[nicktorwald]

Maybe we misunderstood each other. I would leave TarantoolConnection itself for compatibility (say, YSCB use it), but use TarantoolClientImpl in JDBC part of the connector.

Okay, reverted.

[Totktonada]

Please, try to avoid resorting of methods and such changes: it complexes a code review and garbage git blame. If these changes are needed, move them to a separate commit.

I don't have objections in general. Some comments are below.

[Totktonada]

LGTM. Just one comment below.

(Please, don't push until we'll release connector-1.9.2.)