Use entities' selection_box instead of bounding_box to remove more decorations.

# Please enter the commit message for your changes. Lines starting
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# Date:      Sat Jun 1 20:33:53 2019 +0200
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# interactive rebase in progress; onto 945a7cc
# Last commands done (8 commands done):
#    pick 4f25189 add thumbnail.
#    reword 9965d84 Use selection_box instead of bounding_box to remove more decorations.
# Next commands to do (2 remaining commands):
#    pick 86f617f Code reformatted.
#    pick 44e1089 Release.
# You are currently editing a commit while rebasing branch 'master' on '945a7cc'.
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# Changes to be committed:
#	modified:   control.lua
#
