Feature request : Seperate Look-up table from mapping frame data.

[VAdaPEGA]

Splitting the Look-up table from the frames would be useful in order to edit specific cases such as Super Sonic / Sonic and S1's Title Cards / End of Level Tally, for which Mapping tables share sprite mappings and tend to be one of the biggest roadblocks for newcomers to edit.

This would require the ability to load multiple mapping files which might only work with frames having their own labels as requested here https://github.com/kirjavascript/Flex2/issues/102