[vfs] IFile::Read and all derived classes: change to use size_t/ssize_t, do not use more than SSIZE_MAX of buffer for "Read()", small related fixes
[vfs] Change CFile::Read() to use size_t/ssize_t; add checks for "Read()" return values; some fixes for new types in "Read()"; update types in code to match 'ssize_t' returned by 'Read()'; some usage of negative return values for Read()
ZipManager::GetZipList: use auto_buffer, fix improper use of std::string internal buffer
Reflect int64_t -> size_t changes for "Read()" to Addons
[vfs] IFile::Write and all derived classes: change "int Write(void*, int64_t)" -> "ssize_t Write(void*, size_t)"', small related fixes
[vfs] Change CFile::Write() to use size_t/ssize_t; add checks for "Write()" results; check for negative values; update types to ssize_t
Reflect int64_t -> size_t changes for "Write()" to Addons
Merge pull request #4962 from Karlson2k/vfs_update_05_alt
videoplayer: adapt lateness detection and dropping to buffering
video player: present correct pts to user for a/v sync (after buffering in renderer)
videoplayer: update frametime, it might change due to fps detection
videoplayer: give streams with invalid fps a chance for fps detection
dvdplayer: allow rewinding at end of stream, do a seek after rewind
dvdplayer: observe pts counter overflow
dvdplayer: avoid short screen flicker caused by unnecessary reconfigure of renderer
vdpau: advanced settings for auto deinterlacing
player: fix rewind
fix incorrect display of fps when dr kicks in
ActiveAE: slightly reduce buffer size
Revert "vdpau: comment some features that will be added later"

This reverts commit e00b4f65864d623ab4d2e9e5c06db138e661f1cf.