Added search api

[tigrang]

Made changes to formatting and code style as well (please don't hate me)

New features are in NexmoAccount.php

searchMessage($message_id)
searchMessages($ids)
searchMessagesByRecipient($to, $date)

Do you think the search api should be done like:

'search_messages_ids' => array('method' => 'GET', 'url' => '/search/messages/{k}/{s}?ids={ids}'),
'search_messages_recipient' => array('method' => 'GET', 'url' => '/search/messages/{k}/{s}?to={to}&date={date}'),

rather than the third paramater to apiCall I added to append GET parameters to the URL?

[prawnsalad]

Thanks for the additions :)
Could you separate out the new search methods into it's own commit? You have introduced unused methods (object_to_array) and the the style changes is huge in itself. I'd be happy to pull the style + search commits separately.

Adding the 3rd parameter to apiCall() makes sense for these and possibly future methods where they may be optional.

[tigrang]

No problem. I split them into two commits.

There are still some inconsistencies within the code. Most variables use access modifiers, but some still use var.
Some concatenation is done by $one . 'some_text'; and others are $one.'some_text';
Some arrays are written as 'key' => 'value' while others are 'key'=>'value'.

If you want to set a style, I can go in and fix them.

Nexmo also recently came out with a search rejections api so that needs to be added as well. I don't know if I need that right now so I won't be implementing it myself at the moment.

I don't remember why I added the object_to_array (I don't even remember adding it), but it's not needed - I removed it.