Support better child path appending (handling of / is error-prone)

[katowulf]

When I append a child path, I have to remember to prefix it with /; could firebase-php check internally to make sure the / is present? This would also more closely match other Firebase APIs' handling of child paths.

Example:

$fb = new Firebase\Firebase(array(
  'base_url' => 'https://INSTANCE.firebaseio.com/phptest',
  'token' => SECRET,
),new GuzzleHttp\Client());

// this dumps the data for /phptestfoo instead of /phptest/foo :(
// there is no error or indication that the path is wrong
var_dump($fb->get('foo'));

Same is true for all get/set/push/delete et al methods.

[eelkevdbos]

Hi @katowulf, I've added automatic addition of a directory seperator in the case described above and added tests for it. Can you confirm the issue solved?