v0.6.0

• Add feature onpop() callback support
• --toastProgressBackground renamed to --toastBarBackground - old key still works though to maintain backward compatibility
• Replace tooling from standardjs to prettier
• Remove extraneous pausable check from resume()
• Expose more CSS vars:

._toastItem {
  padding: var(--toastPadding, 0);
  border: var(--toastBorder, none);
}
._toastBar {
  top: var(--toastBarTop, auto);
  right: var(--toastBarRight, auto);
  bottom: var(--toastBarBottom, 0);
  left: var(--toastBarLeft, 0);
  height: var(--toastBarHeight, 6px);
  width: var(--toastBarWidth, 100%);
}