Added keydown and focus handlers for Slot Section Menus ("Core Internal", "Optional Internal", etc.)
When focus is on the header, Enter key will open the menu and set focus to either the first option, or else the currently selected option, such as "Planetary Explorer" in Core Internal menu (if one has been previously selected).
While menu is open, Tab and Shift-Tab will move the focus up and down as expected. Shift-tab on first option will move focus to last option in the menu, and Tab on the last option will move focus to the top. Focus will stay inside the menu until menu is closed.
When focus is on a menu options, hitting the Enter key will trigger the onClick function for that option, and will set the option as the currently selected option for that menu.
Esc key will close the menu and set focus to the menu header H1 element.
* Fix to account for cases where there is only one module available for a given slot (e.g. Sidewinder fuel tank)
* Fix for issue #289 - set focus to active module section if the slot has an active module
* Added activeSlot ref to set focus to current module when module list is opened
* Comment/console cleanup for PR #291
* Initial stab at Tab/Enter key handlers for Slots - Added tabIndex="0" attribute for the Slot sections and for the <li> elements inside.
* Set up refs for slot <li> elements to allow focus manipulation.
* Added initial keyDown handlers for Enter and Tab keys.
* Additional update for focus handling inside slot selection <ul>
* Added Tab/Enter/Shift-Tab key handlers for Outfitting section. Needs some fine-tuning but is usable in current state
* Added keydown handler for Empty module selection. ToDo: handlers for engineering sections
* Cleanup
* Update to add focus on Modifications icon and Enter key handler to open modifications menu
* Updates to add keydown handlers for modifications menu, and tab/shift-tab/enter key handlers while mod menus are open.
* Additional updates for keyDown handlers
* Update to add tabindex=0 and Enter Key handling for specials menus. ToDo: keep focus inside specials menu until item is selected with Enter key.
* Further updates for keyDown handler in Modifications menus.
* Added keyDown handlers to full mod menu (when mod menu is opened and a mod has been previously selected)
* Update to add shift-tab and tab focus handling for number editor fields
* Additional tab/shift-tab handlers. Fixed bug with exp. effects being recaculated for every onBlur event.
* Added check to bypass focus reset if change in component was due to change in modification value.
* Additional updates to tab/shift-tab handlers for modifications menu.
* more updates
* "Final" updates and bug fixes - added code for cases where there were no specials.
* Final updates to set focus to appropriate element when slot/mod menus are closed.
