moved min size logic into LLWindow

- Now chiclet bar adjusts its width with Mini-Location bar

EXP-1631 FIXED (Selecting Edit for more than one Pick from Profile floater, breaks the navigation history in Picks Floater)

- Allowed to create a new instance of LLPanelPickEdit for each pick

EXP-1577 FOLLOWUP Making default My Profile window size the same as size of other residents' profile floaters.

It is also now possible to toggle microphone via the menu.

See JIRA for the full list of changes.

EXP-1506 FIXED starting the toast fade timer when a toast is overlapped by other floater like avatar inspector.
This is a kind of a workaround: perhaps the logic of updating the toast fade timer should be refactored to start/stop the timer from onMouseLeave/onMouseEnter callbacks instead of using "IsHovered" flag for each toast.

EXP-1498, EXP-1595, EXP-1596 : Hide empty system folders in a dynamic way, turn the setting ON by default

Per conversation with Product and Leonidas, the minimum size
is now set to 960x600.

Update LLQtWebKit to fix EXP-1191 Update loading overlay graphic to resemble a typical Web loading... spinner

Enable My Profile to use saved_rect.
Value of the "WebProfileRect" setting is ignored in this case.

EXP-1554 FIXED (Selecting More Info for more than one Classified section in Search floater, breaks the navigation history in Picks Floater)

- For each classified info create a new instance of LLPanelClassifiedInfo
- Added destructor for LLPanelProfile::ChildStack to avoid memory leak

- Removed old profile window from People panel with all subpanels and dependencies

- Added "Snapshots" button to 2nd tier default toolbar

EXP-1498 : Always create the folder widget, move empty filtering to foltering code. Still update issues though.

EXP-1498 : Add a debug setting DebugHideEmptySystemFolders which is OFF by default so that we can control showing or hidding of system folders (this is temporary so we unblock testers).

made non-movable floaters not use auto-follow logic
toasts will now use own layout logic

EXP-1498 : Hide empty system folders. System folders can be specifically marked to be hidden if empty in the LLViewerFolderDictionary constructor.

and
EXP-1528 Launching viewer with a settings.xml file with windowwidth and windowheight set below minimum values, launches to those values not minimum window size

Fixed the "Use external browser" radio group to work with its setting properly:
* Specified valid boolean values ("true" and "") for the radio buttons.
* Made default value of the setting boolean to ensure proper initialization.