Correct output of Memory Usage, fix for free_ram, max_ram, used_ram added current_ram

I've also fixed the memory output to display correct values and added the variable "%current_ram%"

PROOF: http://prntscr.com/42q3sp ( differnce of 2mb in free_mem is my speed of print screening after executing the command )
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Long/int division resulted in unexpected values, making sure the value
is in the range of long fixes this problem.

TO DO: Fix used%ram