Cosmetic
Update buildscripts.

Install libs and headers into /mingw{32,64}/{lib,include}
Update gcc_build.

Fix copying bzip2.
Add --enable-checking=release to configure options of gcc. I forgot it.
Update dotfiles/.vimrc.

Now, vim supports breakindent, so I use it.
cpath: Use windows native build of mercurial instead of msys2 one.

This helps building x265.
Update dotfiles.
buildscripts/lsw.sh: Convert lsw_avisynth.log to UTF-8 from CP932.
Update pacman_list.
dotfiles: Add .tmux.conf.