Commands:
- /xpb++ open the menu
- /xpb++ create <type> <multiplier> Manually Active a booster (permission: xpb++.*)
- /xpb++ start <type> <multiplier> <duration> Manually Active an Admin booster (permission: xpb++.*)
- /xpb++ give <player> <type> <amount> Give a booster (permission: xpb++.*)
- /xpb++ take <player> <type> <amount> Take a booster (permission: xpb++.*)
- /xpb++ use <type> Use a booster
- /xpb++ reset <player> <type> take all boosters (permission: xpb++.*)

Placeholders:
- %xpb++_multiplier_<type>% get the active booster multiplier
- %xpb++_timeleft_<type>% get the time left of the active booster
- %xpb++_isboosted_<type>% check if the booster is activated
- %xpb++_whoisboosting_<type>% get the ppl who started the booster
- %xpb++_booster_<type>% get the number of boosters the player has.