add initial support for viewing variants in the sdk config tree. refactor some code which initializes sbsv2 contexts. some hacks added for re-loading configurations when the default config is a variant.

delete help->open on-device connections menu

Fixed problem in isUniqueSDKId() that may cause recursive calls.

initial commit. add a product variant dialog

merge commit

Implement variant support for SBSv2 configuration management. Variants aren't selectable, only the global prefs allow you to create variants, if they exist in an SDK.