add: git changelog gen script

git2debchangelog.sh

@@ -0,0 +1,33 @@
+#!/bin/bash
+#
+# Convert git log into changelog in Debian format
+#
+# Tags in format 1.2.3-4 become version entries. Log entries between them
+# become changelog entries. Merge commits are not excluded, so you probably
+# have to clean up the result manually.
+
+RE_VERSION='^v\?[0-9]\+\([.-][0-9]\+\)*'
+# Assume the name of the current directory is the package name
+PACKAGE=${PWD##*/}
+
+function logentry() {
+        local previous=$1
+        local version=$2
+        echo "$PACKAGE ($version) unstable; urgency=low"
+        echo
+        git --no-pager log --format="  * %s" $previous${previous:+..}$version
+        echo
+        git --no-pager log --format=" -- %an <%ae>  %aD" -n 1 $version
+        echo
+}
+
+git tag --sort "-version:refname" | grep -v beta | grep -v rev | grep "$RE_VERSION" | (
+        read version; 
+
+        logentry $version master
+        while read previous; do
+                logentry $previous $version
+                version="$previous"
+        done
+        logentry "" $version
+)