Added config option to enable/disable WebSockets

[vpiskunov]

Due to WebSockets being refused by the server, a workaround is to disable WSS by default, and enable only when needed & if it is working by passing 'sockets': true to the constructor when creating a new instance (see issue #7 ) NB: typo on commit comment, option name is 'sockets', not 'websockets'

[Diolor]

@vpiskunov do you have your own distribution until and if this gets merged?

[vpiskunov]

I have a forked repo with this patch applied, look at https://github.com/vpiskunov/wunderlist.js

Let me know if you need anything else

[timenengwerda]

@vpiskunov could you compile the wunderlist.sdk.min.js in your forked repo (Or tell me how I can compile it myself) so I can replace my official wunderlist.sdk.min.js with yours (Getting tired of the error message by now ;-))