* Created a function to disable the upgrade existing databases radio button if no databases exist.
* Created helper functions for the upgrade database radio button and new database radio button and abstracted the code accordingly.
* Made changes to helper function names and signatures, and added the enableUpgradeRadioButton() helper function.
* Made some changes to the enableUpgradeRadioButton helper function.
* Made changes to helper functions to ensure the radio buttons enable accordingly when a server is changed from the server dropdown.
* Made changes to helper functions and checks.
* Made additional checks to the populateDatabaseDropdown function.
* Added the logic to select the new radio button when upgrade radio button is disabled.
Srivatsan Vasudevan