dont abort if wait for net fails
webserver: cosmetic refactoring
webserver: add support for If-Unmodified-Since HTTP header
webserver: add Cache-Control HTTP header to cacheable responses
webserver: handle Cache-Control: no-cache and Pragma: no-cache
webserver: use defines for HTTP header fields and values
webserver: silence warning
webserver: refactor IsAuthenticated()
Fix "Current fanart" not being shown in DialogVideoInfo.

I'm not sure why and I didn't investigate further, but a combination of early
unpacking the fanart and accessing the CFileItemPtr in place of the CFileItem
fixes the issue.

(cherry picked from commit 7f1a748935cbd95f638ba03e4d819d3567d71068)
video library: add the possibility to clean the database in the background
music library: add the possibility to clean the database in the background
[vfs/Pipe] - fix premature close of pipe. It should only be closed if
refcount is zero
[pvr] don't update the item list path before calling Update(),
otherwise the history will be incorrectly recorded since the the
history expects m_vecItems->GetPath() to be the "old" path, not the
new one
[gui] update the view state's list reference before the view state is
consulted about whether the "go to parent" item should be added to the
list

Without this the view state will always think the previous directory is
the one you're currently in. This means that e.g. in the recordings
window the "go to parent" was shown in the root directory (except the
first time the window was entered since the path is set correctly then),
but not in subdirectories.
subdirectories.
[addons] add toggle for hiding broken addons. hide by default
vda: fix chroma issue with vda upload

GL_YCBCR_422_APPLE need a GL_RGB internal format not GL_RGBA
vda: cvref textures are non power of two so don't allocate extra space
vda: use IOSurfaceGetPixelformat instead of CVPixelBufferGetPixelFormatType

We have converted the texture to an IOSurfaceRef so use that to check
for format.
vda: allocate pot texture if requested
vda: switch cvref rendering over to standard UYVY422 renderer

This gives brightness/contrast/scaling support. The fallback to
old style upload is dropped since GL_YCBCR_422_APPLE
is no longer used.