[cosmetics] removed unused variables and code
upnp: serialize/deserialize datetime values in W3C format
upnp: improve metadata (artists, albums) for musicvideos
upnp: include musicvideos in list of video items
videodb: use triggers to delete items from link tables
[testsuite] - Remove unnecessary inclusion of filesystem/NFSFile.h - issue #15356
upnp: improve streamdetails
upnp: only set the year from the date if the date is valid
upnp: add support for reading actors
Merge pull request #5021 from mkortstiege/unused

[cosmetics] removed unused variables and code
Merge pull request #5144 from Montellese/upnp_small_improvements

UPnP: improved metadata
[pvr] fix open search dialog in search window

After changing the special item 'Search...' to be a folder (to always
stay on top of the list) the path comparison fails, because the path now
ends with a slash.
Merge pull request #5155 from xhaggi/pvr-fix-open-search-dialog

[pvr] fix open search dialog in search window
Merge pull request #5153 from anthonyryan1/mistaken-nfs-include

[testsuite] - Remove unnecessary inclusion of filesystem/NFSFile.h
Merge pull request #5145 from Montellese/videodb_use_triggers

videodb: use triggers to delete items from link tables
binary addons: only read the URL and revision of an addon if it is built
cmake: use separate_arguments() instead of string(REPLACE) to split a string into a list
binary addons: add platforms.txt to specify the platforms an addon can be built for
cmake: use ${CMAKE_COMMAND} instead of "cmake"
[rbp] Make gui limit default to 720 when memory is limited

On a 256M Pi, it's safest to default to 720p gui as memory is quite limited.