Update LAV Filters to 0.58.2-93-6f44791 (custom build based on 0.58.2-88-6d574b9)

Important changes:
 - Add support for HEVC and VP9.
 - Fix a potential crash in tray icon custom patch: double-clicking on LAV Video/Audio tray icon could lead to crash because of uninitialized pointers.

This commit fixes #3590.
player.html: remove width completely.

It's handled in JS.
temp
Use ZeroMemory on more places instead of {0,0}
Fix NULL handle passed as parameter.
Update Git to 1.8.4.
Cleanup
cleanup
Update SoundTouch to 1.7.2 r173.
MPCTestAPIDlg.cpp: Check return value and add a cast to shut up /analyze.
Minor cosmetic changes.
common.props: Specify _WIN32_WINNT and _WIN32_IE too.
aaaa
Webserver: minor wording changes to the 404.html file.
Webserver: update web/default.css.

* Add normalize.css minified with `cleancss --s1 -b`
* Add box-sizing
* Remove float with display:inline