add obnam (backup software)

Created by: kalos

Stable and very useful backup program. Support: snapshot, de-duplication, encryption

README.md

@@ -64,6 +64,7 @@ A curated list of amazingly awesome open source sysadmin resources inspired by [
 * [Duplicity](http://duplicity.nongnu.org/) - Encrypted bandwidth-efficient backup using the rsync algorithm.
 * [FreeFileSync](http://www.freefilesync.org) - Folder comparison and synchronization tool.
 * [Lsyncd](https://github.com/axkibe/lsyncd) - Watches a local directory trees for changes, and then spawns a process to synchronize the changes. Uses rsync by default.
+* [Obnam](http://obnam.org/) - Easy and secure online and disk-based backup application.
 * [Rsnapshot](http://www.rsnapshot.org/) - Filesystem Snapshotting Utility.
 * [SafeKeep](http://safekeep.sourceforge.net/) - Centralized pull-based backup using `rdiff-backup`.
 * [TarSnap](https://www.tarsnap.com/) - Secure backup service with an open-source client.