Version 0.3.0

• updated ".options" argument to showToast to use the shinyFeedback default options for
  any options not included in the list passed to ".options" (#46)
• new function hideToast() to programmatically hide all toasts (#44)
• simplified and deduped JavaScript (#42) - Thanks @jcheng5!
• added input feedback support for shiny::fileInput() (#41)
• updated "shinyWidgets.AirPickerInput" name to reflect the change to shinyWidgets
• bug fix to maintain all input styles other than the border style applied by
  shinyFeedback when feedback is removed (#36)