Gnuplot script for line plot added

plot-line.plt

+set terminal png       
+set output  "plot-sort-data.png" 
+set title "Computational cost of sorting algorithm"
+set xlabel "Number of elements to sort"
+set ylabel "Time (ms)"
+set style line 1 linecolor rgb '#0060ad' linetype 1 linewidth 2 pointtype 7 pointsize 1.5
+set datafile separator ','
+plot "data.dat" using 1:2 with linespoints ls 1
\ No newline at end of file