moved gains to misc folder

This reverts commit c52c39f.

misc/gains_olci.csv

@@ -0,0 +1,22 @@
+platform,band,wavelength,average_gain,standard_deviation
+A,1,400,0.975458,0.005544
+A,2,412.5,0.974061,0.005897
+A,3,442.5,0.974919,0.005435
+A,4,490,0.968897,0.005645
+A,5,510,0.971844,0.004139
+A,6,560,0.975705,0.003086
+A,7,620,0.980013,0.002107
+A,8,665,0.978339,0.001412
+A,9,673.75,0.978597,0.002128
+A,10,681.25,0.979083,0.001504
+A,11,708.75,0.980135,0.004555
+A,12,753.75,0.985516,0.003723
+A,13,761.25,1,0
+A,14,764.375,1,0
+A,15,767.5,1,0
+A,16,778.75,0.987718,0.00352
+A,17,865,0.986,
+A,18,885,0.986569,0.00176
+A,19,900,1,0
+A,20,940,1,0
+A,21,1020,0.913161,0.008537