[doc] Add script to extract all contributors between two commits

bin/doc/getcontributors.sh

+#!/bin/bash
+
+help()
+{
+   echo "Prints all commit authors (contributors) between two commits."
+   echo "Usage: $0 -from <commit sha or tag> -to <commit sha or tag>"
+   echo "Example: $0 -from 2.12.0 -to d9efb9d80b1f794d976f6b5ae1ffb9f71a7dcdf9"
+   echo -e "\t-from From where: The commit sha or other tags working with git log"
+   echo -e "\t-to To where: The commit sha or other tags working with git log"
+   exit 1 # Exit script after printing help
+}
+
+if [[ $# -eq 0 ]]
+then help;
+fi
+
+while [[ $# -gt 0 ]]
+do
+key="$1"
+
+case "$key" in
+    -from|--from)
+    from_sha="$2"
+    shift
+    shift
+    ;;
+    -to|--to)
+    to_sha="$2"
+    shift
+    shift
+    ;;
+    ?)
+    help # print help
+    ;;
+esac
+done
+
+echo "Contributors from commit ${from_sha} to ${to_sha}:"
+
+git log $from_sha..$to_sha "$@" | grep ^Author: | sed 's/ <.*//; s/^Author: //' | sort | uniq -c | sort -nr