NBT Autocomplete

===Version 2.1===
-Added /data command storage suggestions.
-Added support for @s selector (thanks to W2D3F1X2 for reporting).
-Restored ability to load user-defined suggestions (thanks to UnRealDinnerbone for request).
-Added getValueSuggestions() API method (thanks to mega12345mega for suggestion).
-Improvements to loading suggestions with API. Added addBlockEntityMapping() API method.
-Suggestions based on entity selector now work for any valid player name, not only of these within render distance.
-Removed "support_command_namespace" and "use_new_thread" settings while keeping their default (enabled) behavior.
-Removed setting sections "Mods and Plugins Support" and "Advanced Settings" - "unknown_item_components" was moved to "Item Components".
-Fixed missing "block to block entity" mapping on later versions.
-Fixed missing suggestion for brewing_stand "Fuel" tag.
-Fixed missing Polish translation for "unknown_item_components" setting description.
-Added "nbt_ac" (1.x version) as incompatible mod (thanks to lunaynx for reporting).