Updated CLSCORE:Reopen() to CLSCORE:Toggle()

See: https://github.com/Facepunch/garrysmod/commit/9a2273218d37c3357c4ca7a89d790d5dcbcb9c26#diff-6584fbd605c43889286045f89e710fc5

- set items as favorites to show them at the top of the list
- enable/disable markers on items (slot-, custom-, favorite-marker)
- minor text tweaks

- added serverside ConVars to allow/forbid custom layouts (ttt_bem_allow_change)
- added serverside ConVars to set layout for everyone (ttt_bem_sv_rows, ttt_bem_sv_cols, ttt_bem_sv_size)
requested by MomoMB

- moved settings menu to f1 menu

- added ConVar for item size: ttt_bem_size (def. 64)
- added ConVar for row count: ttt_bem_rows (def. 5)
- added BEM settings tab for changing above ConVars (see Screenshot)

Please report any issues with the update in the discussion thread

added ConVar to set column count (thanks to Gamefreak for the suggestion and help]