Bugfix #961. beforeColumnSort and afterColumnSort event listeners can now be defined in HOT constructor. Events will be fired only when sortColumn is defined (it prevents firing events on plugin init).
Added "filter" option to autocompleteEditor, which controls whether choices list should be filtered according to the value of editor's textarea.
Cleaned autocomplete demo
Highlighting items in autocomplete list now works the same as in Gmail's lists
Added Dropdown editor
Added ability to navigate through context menu using keyboard keys.
Fixed menu positioning when page is scrolled
Enhanced keyboard navigation in contextMenu. Disabled items are now skipped during navigation. Enhanced code readability.
Tests for context menu keyboard navigation
Removed style for :hover on context menu item.
Removed TODO.
getCellRenderer, getCellEditor, getCellValidator
remove legacy syntax for setting renderers, editors, validators: `{type: {renderer: ... }}`, now only flat syntax is valid: `{renderer: ... }`
Attempt to run cell menthod getters in IE - unsuccessful
Fixed modifying columns object while expanding type property.
Fixed demo/renderers_html with header menu
Merge branch 'feature/cellFunctionsGetters' into customHeaderRendererDemo

Conflicts:
	src/core.js
if method does not exist (eg. validator), returns undefined. TODO write test that overwriting type "numeric" with type "text" also overwrites numeric validator with undefined in cellProperties
fix demo in IE8, revalidate cells before render
numeric validator should validate null with the same empty string