add support for query_all in api version 29+

I stumbled across a new surprise feature of the Salesforce rest api.  The query endpoint doesn't return
1. Deleted records (even those still in the soft-deleted or recycle bin state.  
2. Archived records (tasks and events are archived automatically by Salesforce, based on some very complex rules)

according to http://www.salesforce.com/us/developer/docs/api_rest/index_Left.htm#CSHID=resources_queryall.htm|StartTopic=Content%2Fresources_queryall.htm|SkinName=webhelp

the QueryALL rest endpoint is available in api version 29.0 or later.  This will give us both soft-deleted and archived records. I opted to add a query_all method on concerns/api, so the existing behavior for query would not change.