Chinese takeaway

After a loooong beta process, many bugs have been solved, new features added, and a few easy to fix breaking changes happened.

• [BREAKING CHANGE] Passing class="my-foo" to the component just customizes the class of the top-most
  component, but doesn't try to derive classes from it for the trigger and the dropdown. This behavour
  was unexpected, confusing, didn't work with multiple classes class="foo bar baz" and doesn't enables
  any feature that triggerClass= and dropdownClass= don't allow already. Ditched.
• [BUGFIX] Allow to type in closed multiple selects. Before the default behaviour of keydown events
  was being prevented, disallowing the typing.
• [BUGFIX] Ensure the public API passed to the components and to the ourside world is the same, by
  making it a CP and and use it as single source of truth.
• [BUGFIX] Fix a bug filtering when the given options is a promise.
• [ENHALCEMENT] The custom matchers defined by the user now can and should return numbers instead of
  true/false. Returning a boolean still works but emits a deprecation warning and will be removed in the next version.
  The reason is that returning a number gives us more posibilities, like sorting the results.
• [BUGFIX] Ensure the placeholder text of simple selects doesn't overflow the container trigger.
• [FEATURE] Allow to customize the destination element used by ember-wormhole on a per-component basis
• [FEATURE] Update to ember-basic-dropdown 0.9.0 final. This allows to customize the wormhole destination
  of all dropdowns of the app, including ember-power-select's dropdowns.
• [BUGFIX] Ensure triggerComponent receives the loading property to allow showing spinners and things like that.
• [BUGFIX] Ensure beforeOptionsComponent and afterOptionsComponent receive the extra object.
• [FEATURE] Now you can type in closed single selects and automatically select the first match as you type.
  The typed text is erased after one second. It doesn't work in closed multiple select without searchbox (what would be the correct behavior?)
• [FEATURE] Now you can type in opened selects witout searcbox (multiple or single) to highlight the
  first marching option as you type. The typed text is erased after one second.
• [FEATURE] Search can be disabled in multiple selects, instead of only in single selects.
• [BUGFIX] Pressing enter in a select without searchbox correctly selects the highlighted element
• [FEATURE] Proper Accesibility!! Lots of roles and aria-* tags have been added to make the component
  friendly, according with the guidelines in the RFC
• [BUGFIX] When the component received a promise as options and also a search action, clearing
  the search must show the content of that promise.
• [FEATURE] The .ember-power-select-options added to wrap the noMatchesMessage and the searchMessage
  have special classes to help styling them (ember-power-select-option--no-matches-message & ember-power-select-option--search-message)
• [BUGFIX] Single selects without searchbox can be focused normally. Fixed updating ember-basic-dropdown.
  Ember basic dropdown was calling preventDefault on the mousedown event to prevent the user to
  select text when moving the mouse between the mouseup and the mousedown. Now the event is not defaultPrevented,
  it uses another technique.
• [BUGFIX] When the list of options is empty but the component is given a search action, it should
  not show the No results found until the user actually performs a search and there and it comes
  empty.
• [BREAKING] The ember-power-select-options--nested class is not used anymore. Now nested groups
  have role=group, and the top-most one has role=listbox.
• [BREAKING] The *--open class on the .ember-power-select div has been removed. Now styles
  target [aria-expanded=true/false], and it applies to the trigger, not to the top-most div.
  People explicitly targeting this class in they styles will need to update.
• [BREAKING] Warning. Classes ending in --disabled, --highlighted and --selected have been
  replaced by aria attributes [aria-disabled="true"], [aria-current="true"] and [aria-selected="true"]
  respectively. Those attributes are needed for a11y and the recomendation is to style based on them
  instead of classes.
  Styles have been updated accordingly, so people using them and customizing the appearance using the
  sass variables won't notice anything, but people that relied on those classes for overriding styles
  will have to update them.
• [TESTING] Run fasboot tests as part of CI
• [TESTING] Add fastboot tests harness.
• [FEATURE] Initial Fastboot support!!
• [INTERNAL] Removed deprecated properties
• [INTERNAL] Updated mirage, liquidfire, ember-try and others.
• [FEATURE] $ember-power-select-line-height variable can have units now.
• [IMPROVEMENT] Multiple select's trigger uses flexbox to improve appearance and behavior. In browsers
  without flexbox works as it did before.
• [FEATURE] Multiple selects have a distintive class in the trigger so they be styled accordingly.
• [BUGFIX] Modify the searchText programatically (through the select.actions.search('foo') per example)
  updates the input, respecting the cursor position.