Refactor exception.h, rename methods
Clear framebuffer on each frame in main.cc
Remove unused `buttons` variable from main.cc
Port to SDL2, refactor main.cc
Use vector instead of unique_ptr + length
Use `emplace_back` in PAK3Archive
Rename zipfile to archive
Make ZIPArchive::read_file exception safe
Make main window resizable
Remove ImageMagick++ dependency, use SDL2_image
Add Makefile dependencies
Use POSIX clock_* functions for more precision
Tweak movement, fov, fps limit
Add binio.{cc,h}, binary IO helper/wrapper class
Refactor BSP classes, make loading endian-safe
Cosmetic changes in image.cc