feat(adjust-height): improve adjust-height to support custom margin bottom and specifying container

* Use 'w11k-select-adjust-height-to' as class on an element to specify a container element the auto-adjust-height feature will use.
* Use 'w11k-select-style' as attribute to pass an object with styling information to the directive. You can reference an object in scope or use literal notation (like ng-style)
  Supported properties: maxHeight (all units) and marginBottom ('px' only)
doc(demo): add demo of w11k-select-style
chore(grunt): improve readability of uncompressed js file in dist
fix(adjust-height): do not extend height greater than window
fix(adjust-height): hide dropdown menu until adjust-height finished to avoid flicker
fix(adjust-height): fix calculated height
fix(filter): fix getting focus after opening drop-down
chore(select): optimise code for minification
feat(config): make everything configurable via constant w11kSelectConfig and w11k-select-config attribute

Take a look at the source code and comments of w11kSelectConfig to see all configurable variables.

BRAKING CHANGE:
Following attributes are no longer available:
* w11k-select-multiple
* w11k-select-selectedMassege
* w11k-select-filter-placeholder
* w11k-select-placeholder
* w11k-select-disabled
* w11k-select-required
* w11k-select-style

Use constant w11kSelectConfig  and the new w11k-select-config attribute to configure the directive.
doc(demo): adjust demo to new configuration attribute
doc(readme): adjust readme to w11k-select-config