add readme and status file

Readme.md

@@ -0,0 +1,13 @@
+# Mysql backup
+
+create dump of all mysql databases, one file per database
+
+including grants
+
+backups done in /root/backups/mysql - you can pass it another dir as argument too
+
+depends on a default files (default /root/.my.cnf) containing credentials
+
+Keeps 15 (can be changed)  days of backup
+
+create a status file containing exit code (you should monitor that file mtime and content)