Buddylist changes: remove bytes sent/received and userId, show giving/sharing icons, code cleanup

Changes for https://github.com/uProxy/uproxy/issues/622 (Better display of active buddies)

* Remove bytes sent/received
* Remove userId
* Show giving/sharing icons next to the user name
* Code cleanup:
 * Making variables private in ui.ts where possible
 * Moving more UI logic into startGettingInUiAndConfig and stopGettingInUiAndConfig, rather than having multiple UI update methods that need to be called.
 * Now mapping in the UI from instanceId to user, rather than instanceId to userName

Tested in Chrome, Firefox (UI loads), updated grunt test
are there todos to rename at least one of these. this seems like a pretty non-ideal situation