Configurable Guzzle client timeout

[litencatt]

Now Guzzle client timeout is set fix value 5.0 in Notifier::postNotice().

faultline-php/src/Notifier.php

Lines 63 to 72 in 0253bb6

	protected function postNotice($url, $notice)
	{
	$client = new Client();
	$config = [
	'headers' => [
	'Content-Type' => 'application/json',
	'x-api-key' => $this->opt['apiKey']
	],
	'json' => $notice,
	'timeout' => 5.0,

But we want to change timeout value.
So this PR changes Guzzle client timeout to configurable.

[k1LoW]

@litencatt Thank you for your NICE WORK!!!!

[k1LoW]

Released as v0.7.0.