This update brings Codex to 1.21.5

Apr 28: Bumped nexo from 1.5.0-dev.2 to 1.5.0-dev.13
May 4: Bumped nexo from 1.5.0-dev.13 to 1.6.0-dev.1
May 11: Bumped nexo from 1.6.0-dev.1 to 1.6.0-dev.13
May 18: Bumped nexo from 1.6.0-dev.13 to 1.7.0-dev.1
May 26: Bumped nexo from 1.7.0-dev.1 to 1.7.0-dev.4
May 30: Fixed prev button and added clear-slots option
May 31: Tagged build 1.1.1-R0.1-SNAPSHOT
Jun 1: Updated to 1.21.5
Jun 1: Tagged build 1.1.1-R0.2-SNAPSHOT
Jun 2: Bumped nexo from 1.7.0-dev.4 to 1.8.0-dev.6
Jun 8: Bumped worldguard-bukkit from 7.0.9-SNAPSHOT to 7.0.13
Jun 8: Bumped worldedit-bukkit from 7.3.9-SNAPSHOT to 7.3.14
Jun 8: Bumped worldedit-core from 7.3.9-SNAPSHOT to 7.3.14
Jun 8: Bumped nexo from 1.8.0-dev.6 to 1.8.0-dev.17
Jun 9: Merged worldedit-core bump
Jun 9: Merged worldguard-bukkit bump
Jun 9: Merged worldedit-bukkit bump
Jun 9: Merged nexo bump to 1.8.0-dev.17
Jun 15: Bumped nexo from 1.8.0-dev.17 to 1.8.0-dev.25
Jun 23: Bumped nexo from 1.8.0-dev.25 to 1.9.0-dev.5
Jun 30: Bumped nexo from 1.9.0-dev.5 to 1.9.0-dev.12