feat(toast): add actions, behaviors and other variations

BREAKING CHANGE: contains some breaking changes to the core logic and settings.

New Features
  - Image support just like icon
  - displayTime 'auto' calculates time by amount of words
  - Progressbars can have its own individual color now 
  - A toast can be created out of existing dom nodes or markup now $('.ui.toast').toast() with clone support;
  - Toast is pausable on hovering to be able to mark/copy text or just hold on to have more time to read it
  - closeIcon can be displayed to the left 
  - Support for `card` and `message` layouts

Behaviors
  - get or check for existing toasts
  - stop/start display timer
  - get the remaining Time

Actions
  - a toast can have a configurable amount of action buttons
  - support for default button selectors as in modal
  - displayable at the bottom of the toast as in modal or full width attached to the modal
  - also displayable to the right

Changed defaults (aka breaking changes)
  - Toast is floating (aka has a shadow)
  - Progressbar decreases
  - Close-Easing is smoother instead of bouncy (still available for those who like it)
  - Icon is centered vertically
  - Toast display in neutral white background without icon (looks good, as it has a shadow now)
  - A possible given title is a bit larger than before (by using standard "ui header")
  - floating and hoverfloating moved from toast to toast-box to cover the whole toast including possible attached actions

Core
  - Changed progressbar from css transition to css animation to be able to pause scrollbar on hover via css only
  - Return instance of created toast even when created dynamically via body so you can interact with and reference it via javascript afterwards
  - Support behaviors because of instantiation
  - Optimized LESS Code usage, refactored JS

Closes #160 #280 #315 #316 #566