AppSettings: Unbind "switch zoom" by default.

Rarely used feature, but easy to accidentally activate in which case it will confuse users.
player.html: remove width completely.

It's handled in JS.
Initialize variables in the constructor.
Enable per-monitor DPI-aware on Windows 8.1.

Fixes #3356.
temp
Add a Doxyfile to generate source doc.

WIP
Losslessly compress res/web/img.
Whitespace cosmetics.

Remove unneeded spaces and reindent comments in some cases to improve readability.
Update Changelog.txt.
pre-commit.sh: use 2 spaces for indentation.