* [sqllab] add support for results backends
Long running SQL queries (beyond the scope of a web request) can now use
a k/v store to hold their result sets.
* Addressing comments, fixed js tests
* Fixing mysql has gone away
* Adressing more comments
* Touchups
* Query search page under SQL Lab tab
* Modifications based on comments
* Hash
* Added spec and endpoint test with modifications
based on second round comments
* Changed permission menu in https://github.com/airbnb/caravel/pull/1095/files
* Query search page under SQL Lab tab
* Modifications based on comments
* Hash
* Added spec and endpoint test with modifications
based on second round comments
* Changed permission menu in https://github.com/airbnb/caravel/pull/1095/files