First commit.
Early draft.
Format code. #mania
Add the -c/--clean option.
Do not recompute layout each time. #performance

We use setOutputStream() and removeOverlay() to save layout parsing each
time.
Add the composer.json.
Add the README.md.
Add scripts in composer.
Remove "forum" entry.
Use online resources.
Remove a useless instruction.
Update Composer compatibility.