Fix crash when entering guidance mode

Do not create a QCheckBox on the stack.

BUG:336771
REVIEW:119069
SVN_SILENT made messages (after extraction)
SVN_SILENT made messages (.desktop file)
SVN_SILENT made messages (after extraction)
Avoid Qt 5.3 "file not found" warnings in TileLoader

REVIEW: 119097
API cleanup
A seek range between 0 and tour duration is more intuitive for the API
Don't crash when an update has no change
Remove unused stuff. Fix memory leaks.
Have parent default to 0
Add a C++ example that creates a HD video screencast from a KML tour
SVN_SILENT made messages (.desktop file)
introduce docked placemark info widget

Viewing placemark information such as Wikipedia articles is currently done via a floating dialog. While it apprears quite
stylish, it covers nearby items such that they can't be clicked or it is moved out of scope when the globe is rotated.
These two properties of the floating dialog get in the way when exploring the world.

To improve the browsing experience, a dock widget containting a web view is used. In order to visually associate the view
with an item, a thin line is drawn between them. This improves the browsing experience since the dock widget always remembers
the last position and size no matter how the user scrolls around or clicks different items. It also doesn't cover nearby
items. As a result, exploring Wikipedia articles and photos is much more addictive.

This patch is still work in progress. As such, it has of course issues such as the line being always drawn or the line not
following the corner of the dock widget. Still, I want to get feedback if the general direction is right. Also, the dock
widget should probably only be used for detailed placemark information, but not e.g. for balloon-style information. Note that
even if I temporarily abused the PopupLayer to power the dock widget, I don't intend to remove PopupItem altogether (it could
still show balloon-style information).

I'm looking forward to your feedback!
activate Panoramio plugin
jsonparser
add config dialog
cleanup
PopupLayer
adjust
tiling