Options hash, api_version, and updated test / readme

[jmagoon]

I've made a change to the API to take an optional hash to the update/upsert/insert/delete/query methods as the last parameter that allows the users of the gem to set their own options, as opposed to them being hidden / unnamed inside the method signatures.

Instead of having to do this to set the timeout:

create('Account', records, false, false, [], 10000, 100) 

You would pass an options hash:

create('Account',records,{:timeout => 100})

All other parameters are set with the current default settings based on the method (e.g. query has :get_response => true by default), and there is a new parameter called :concurrency which allows the user to set their processing method (parallel or concurrent).

An additional change is to rely on the client for the api_version, instead of setting a constant on initialize. This allows the user to set their own api_version based on their own needs.

Finally, I've updated the readme and tests to reflect these changes, along with fixing a few tests that no longer worked after some previous commits.