Remove record data index sorting not really needed

[DanSava]

Issue
Index sorting is also prone to issues when sorting ints that have been converted to strings

Resolves: #195

[frode-aarstad]

I am not really able to reproduce what this was supposed to fix. I remember @DanSava showing a webviz plot that had this problem when discussing perfomance. Could you please tell me how you made that dataset.

[oysteoh]

I am not really able to reproduce what this was supposed to fix. I remember @DanSava showing a webviz plot that had this problem when discussing perfomance. Could you please tell me how you made that dataset.

At least I can reproduce and verify it is actually working. I edited the poly-case to run ensemble_experiment with 20 iterations instead of 10. In the Plot Viewer select the ensemble and then the response poly_res@0. Without Dan's fix i will get the x-axis like this 0, 1, 10, 11 ... 19, 2 .. 9 - with Dan's fix it is in the correct order.