Functions mysql_get_timeout_value and mysql_socket_get not exported

First, according to [1] functions:

mysql_get_timeout_value
mysql_get_timeout_value_ms
mysql_get_socket

can be "used to get the socket fd and timeout values when waiting for events to occur"

But they're not exported into libmysqlclient (not tested, because we use our own list of functions, but they're not listed in [2]).

I think these functions should be exported if they're expected to be used.

[1] https://kb.askmonty.org/en/non-blocking-api-reference/
[2] http://bazaar.launchpad.net/~maria-captains/maria/5.5/view/head:/libmysql/CMakeLists.txt

Second, a typo in [1]: mysql_get_timeout_value is listed twice, the second should be mysql_get_timeout_value_ms..