To get the "mod" in your world get a command block by: /give @p command_block then paste in the command and activate the command block.
I suggest that when you use this command set your worldspawn near the machine by: /setworldspawn
then the command will work anywhere in the world and it will not lagg so much if you go away from the machine so it is not in your chunks.

This command is very owerpowerd but if you name a clock: TimeStopper it will stop the time if you select it.
To start time again name a clock: TimeStarter and select it.

plz give me credit if you are using this I have worked hard for this command!

command:
/summon FallingSand ~ ~1 ~
{Block:redstone_block,Time:1,Riding:{id:FallingSand,Block:command_block,TileEntityData:{Command:fill
~ ~0 ~1 ~ ~-9 ~1
redstone_block},Time:1,Riding:{id:FallingSand,Block:command_block,TileEntityData:{Command:setblock
~ ~3 ~1
stone},Time:1,Riding:{id:FallingSand,Block:command_block,TileEntityData:{Command:setblock
~ ~4 ~ command_block 0 replace {Command:fill ~ ~2 ~ ~ ~-13 ~1
air}},Time:1,Riding:{id:FallingSand,Block:command_block,TileEntityData:{Command:/scoreboard
objectives add Timestop
dummy},Time:1,Riding:{id:FallingSand,Block:command_block,TileEntityData:{Command:/summon
FallingSand ~2 ~ ~-1
{Block:command_block,TileEntityData:{Command:/execute
@a[score_Timestop=0] ~ ~ ~ gamerule doMobSpawning
true},Time:1,Riding:{id:FallingSand,Block:command_block,TileEntityData:{Command:/execute
@a[score_Timestop=0] ~ ~ ~ gamerule doFireTick
true},Time:1,Riding:{id:FallingSand,Block:command_block,TileEntityData:{Command:/execute
@a[score_Timestop=0] ~ ~ ~ gamerule randomTickSpeed
300},Time:1,Riding:{id:FallingSand,Block:command_block,TileEntityData:{Command:/execute
@a[score_Timestop_min=1] ~ ~ ~ entitydata @e[type=Creeper]
{Fuse:800}},Time:1,Riding:{id:FallingSand,Block:command_block,TileEntityData:{Command:/execute
@a[score_Timestop_min=1] ~ ~ ~ gamerule naturalRegeneration
false},Time:1,Riding:{id:FallingSand,Block:command_block,TileEntityData:{Command:/execute
@a[score_Timestop_min=1] ~ ~ ~ entitydata @e {NoAI: 1,Silent:
1}},Time:1,Riding:{id:FallingSand,Block:command_block,TileEntityData:{Command:/execute
@a[score_Timestop_min=1] ~ ~ ~ gamerule doDaylightCycle
false},Time:1,Riding:{id:FallingSand,Block:command_block,TileEntityData:{Command:/scoreboard
players set @a Timestop 1
{SelectedItem:{id:minecraft:clock,tag:{display:{Name:"TimeStopper"}}}}},Time:1,}}}}}}}}},Time:1,Riding:{id:FallingSand,Block:command_block,TileEntityData:{Command:/summon
FallingSand ~2 ~ ~1
{Block:command_block,TileEntityData:{Command:/execute
@a[score_Timestop=0] ~ ~ ~ entitydata @e[type=Creeper]
{Fuse:30}},Time:1,Riding:{id:FallingSand,Block:command_block,TileEntityData:{Command:/execute
@a[score_Timestop=0] ~ ~ ~ gamerule naturalRegeneration
true},Time:1,Riding:{id:FallingSand,Block:command_block,TileEntityData:{Command:/execute
@a[score_Timestop=0] ~ ~ ~ entitydata @e {NoAI: 0,Silent:
0}},Time:1,Riding:{id:FallingSand,Block:command_block,TileEntityData:{Command:/execute
@a[score_Timestop=0] ~ ~ ~ gamerule doDaylightCycle
true},Time:1,Riding:{id:FallingSand,Block:command_block,TileEntityData:{Command:/execute
@a[score_Timestop_min=1] ~ ~ ~ gamerule doMobSpawning
false},Time:1,Riding:{id:FallingSand,Block:command_block,TileEntityData:{Command:/execute
@a[score_Timestop_min=1] ~ ~ ~ gamerule doFireTick
false},Time:1,Riding:{id:FallingSand,Block:command_block,TileEntityData:{Command:/execute
@a[score_Timestop_min=1] ~ ~ ~ gamerule randomTickSpeed
0},Time:1,Riding:{id:FallingSand,Block:command_block,TileEntityData:{Command:/scoreboard
players set @a Timestop 0
{SelectedItem:{id:minecraft:clock,tag:{display:{Name:"TimeStarter"}}}}},Time:1,}}}}}}}}},Time:1,Riding:{id:FallingSand,Block:command_block,TileEntityData:{Command:gamerule
commandBlockOutput
false},Time:1,Riding:{id:FallingSand,Block:command_block,TileEntityData:{Command:fill
~2 ~-2 ~ ~2 ~6 ~
redstone_block},Time:1,Riding:{id:FallingSand,Block:command_block,TileEntityData:{Command:setblock
~2 ~-1 ~-1 command_block 0 replace {Command:fill ~ ~ ~1 ~ ~8 ~1 stone 0
replace
redstone_block}},Time:1,Riding:{id:FallingSand,Block:command_block,TileEntityData:{Command:setblock
~2 ~ ~1 command_block 0 replace {Command:fill ~ ~ ~-1 ~ ~8 ~-1
redstone_block 0 replace
stone}},Time:1,Riding:{id:FallingSand,Block:stone,Time:1}}}}}}}}}}}}