DOC: Update application documentation as well

Modules/Applications/AppClassification/app/otbSampleSelection.cxx

@@ -92,8 +92,10 @@ private:
       " so that the smallest one is fully sampled.\n"
       "  - constant : select the same number of samples N in each class" 
       " (with N below or equal to the size of the smallest class).\n"
-      "  - byclass : set the required number for each class manually, with an input CSV file" 
+      "  - byclass : set the required number for each class manually, with an input CSV file"
       " (first column is class name, second one is the required samples number).\n\n"
+      "  - percent: set a target global percentage of samples to use. Class proportions will be respected. \n\n"
+      "  - total: set a target total number of samples to use. Class proportions will be respected. \n\n"
       "There is also a choice on the sampling type to performs : \n\n"
       "  - periodic : select samples uniformly distributed\n"
       "  - random : select samples randomly distributed\n\n"