Phase zero

- [X] Handwritten bindings

Phase 1

- [X] Parse headers
- [ ] Generate types (QtCore, QtGui, QtWidgets only)
- [X] Rename package
- [ ] v0 Public release

Phase 2

- [ ] Port examples from other Go Qt bindings
- [ ] `connect`
- [ ] Other Qt packages
- [ ] Document use for Windows/macOS/Linux

Wishlist

- [ ] Subclassing
- [ ] Custom Q_PROPERTY support
- [ ] uic implementation
- [ ] Use clang ast's `mangledName` to make a dlsym/LazyDLL cgo-free version