Add "busydialogdelayms" advanced setting.

Provides control over the delay until busy dialog is shown when starting
video playback.
Added a boolean condition to identify the Raspberry Pi platform (System.Platform.Linux.RaspberryPi)
remove old unused renderer files
Fix memory leak in SurfaceFlinger.

Call native_window_api_disconnect to free the memory used by OMX video decoder.
Or, there is memory leak in SurfaceFlinger after a stream playback is stopped.
[Players] Avoid jumping volume to maximum after trickplay
For players that control volume, if the speed changes (e.g. with ff/rew) the volume gets reset to maximum.
This change sets it back to current value, although I question why it is being changed at all.
Do any players require muting during trickplay?
cosmetic: move CGUIControlFactory::GetDimension private
[guilib] fixed - groups with no <width> or <height> set but with <posx> or <posy> had incorrectly derived width or height.
[guilib] adds control positioning via <left>, <top>, <right>, <bottom>, <centerx> and <centery>.

The <posx>, <posy>, <width> and <height> are derived.
Also allows for percentage sizing/positioning, e.g. <left>25%</left>
[guilib] changed: move right aligned label hack so that <left> and <right> behave the same for all controls.

Note: <posx> will still behave as it did in Frodo:
 * On label controls outside of containers that are right aligned, it's the RIGHT edge.
 * In all other cases (including labels inside containers), it's the LEFT edge.
ActiveAE: make viz not observe volume and mute
FIX: [droid] cleanup assets before build and reinstall (possible fix for #14565)
Improve settings locking precision

1) Switch to R/W locks for CSettingsManager
2) Add separate section for settings map and other parts of
CSettingsManager
3) Add locking for CSettings
droid:jni, extend input device handling
droid: add controller/gamepad handling
FIX: Enable Hat handling in Application::ProcessJoystick
FIX: [droid] proper joystick Hat support
Merge pull request #2973 from LS80/master

System.Platform boolean condition for RPi
Merge pull request #3451 from jmarshallnz/control_positioning

Control positioning
[confluence] cosmetic - whitespace cleanup
[confluence] no need to use &quot; inside XML values