Fix HTTP timeouts for SSL connections

CertValidatingHTTPSConnection did not implement the http.HTTPConnection timeout argument correctly.  Newer Botos appear to use this connection instead of httplib.HTTPSConnection which breaks the [Boto]/http_connection_timeout configuration setting.

This patch sets the timeout on the new SSL socket if it has been configured.
Make proxy_ssl used configured timeout

The proxy_ssl method does not use the Boto [Boto]/http_connection_timeout setting when creating its socket.  This patch will configure the requested timeout if it is set in the http_connection_kwargs parameter.
Merge branch 'patch-3' of git://github.com/g2harris/boto into g2harris-patch-3
Merge branch 'develop' of github.com:boto/boto into develop