Check if the args is a valid JSON object

* Since args has `id` as type we need to ensure that is a valid JSON,
otherwise an exception will be thrown.
* It also add an enum for the error code
Check that the error's indirect pointer is valid
Add .DS_Store to gitignore
The JSON validity check should be done on the whole message not just the args
Change the data from NSMutableDictionary to NSDictionary

There is no need to use a mutable version. (Check using the provided
test suite and there is no regression)
Rename the socket state from az_socket_not_connected toaz_socket_disconnected

This is done to be more consistent with the socket.io specs
Rename the AZSocketIOState enum item to be more consistent with the cocoa code convetiont

In the cocoa touch framework usually the enum items name is prefixed
with the type name.
Add the disconnecting socket state

According the socket.io specs the the possible states for the socket
are `disconnected`, `disconnecting`, `connecting`, `connected`.
In this case when the `[AZSocketIO disconnect]` is called the socket
goes in the state AZSocketIOStateDisconnecting while asking to the
transport to effectively close the connection, after that the socket
will be in the AZSocketIOStateDisconnected state.
Merge pull request #7 from lukabernardi/master

Check if the args is a valid JSON object
Merge pull request #8 from lukabernardi/feature/socket.io_spec_state

Conform the AZSocket.io state to the socket.io spec
Merge pull request #6 from oliland/master

Parse JSON on a background thread
Added Oli and Luca as contributors
Add callbacksForEvent:

This method return all the callback blocks associated to a specific
event.
Fix an issue that will crash if messageRecievedBlock or eventRecievedBlock were not set

Signed-off-by: Luca Bernardi <luka.bernardi@gmail.com>
Add namespace support

Signed-off-by: Luca Bernardi <luka.bernardi@gmail.com>
Add more test for namespace feature

Signed-off-by: Luca Bernardi <luka.bernardi@gmail.com>
Merge pull request #9 from pashields/feature/namespace

Add support for the namespace
Add test to check the issue #10

Signed-off-by: Luca Bernardi <luka.bernardi@gmail.com>
Fix #10

In emit:args:error:ack:argCount: if no args is provided we just send the eventName

Signed-off-by: Luca Bernardi <luka.bernardi@gmail.com>
merged with pashields