Added links, reformatted nosql

I added several links to various areas, and reformatted the nosql
section to show the types of noSQL engines.
Add Backupninja backup tool
Add Duplicity backup tool
Merge pull request #65 from clochix/patch-1

Add Backupninja backup tool
Merge pull request #66 from clochix/patch-2

Add Duplicity backup tool
Adding Haraka to SMTP servers.
Merge pull request #69 from caffeinewriter/master

Adding Haraka to SMTP servers.
Fix typo
Merge pull request #70 from eiriksm/patch-1

Fix typo
Merge pull request #67 from freeman512/master

Added Galera SQL
Merge pull request #71 from freeman512/master

Added OTRS
Added Gogs git server.
Suggest DREBS to the backup section

http://dojo4.com/blog/aws-ebs-backups-we-rewrote-drebs for more info.
Adding mesos under cloud computing: http://mesos.apache.org/
Added Postgres-XL

http://www.postgres-xl.org/
Updated README.md: Added OpenTSDB
Adding Docker: An open platform for distributed applications for developers and sysadmins.
Removed docker: duplicate
Update README.md: Added Heka

# closes #72
added emacs to editor suggestions