Add cloud provider APIs for deleting and renaming cloud variables. Remove dataIndex from writeToServer function since it is not used.

Fix issue where regular cloud variable messages were throwing uncaught Json parse errors because of a newline being at the end of the message. Add test that fails without the bugfix.

Uses randomized duration between [0, 2^k-1] where k is the connection attempt number, maxed out at 5.

I had to rework the tests quite a bit to make this easy to test, to work around the timeouts and the randomization.

Refactor cloud manager hoc to use component lifestyle methods to control cloud connection. Abstract our connection creation logic into a funciton. Make canUseCloud check a function.

Move cloud connection logic into its own HOC and add canUseCloud flag to control whether to show the new cloud variable options in the variable modal.

Added a unit test and covered the other case (not used) where you might be trying to update the index zero of a list