remove useless doc

documentation/comparison_to_PaaS.md

-# How do we compare to other PaaS
-
-(Work in progress)
-
-## IndieBox
-
-## Michiel docker bash
-
-And all the one from docker:
-https://github.com/weihanwang/docker-ecosystem-survey

documentation/recover_from_backup.md

-```
-# upload the key
-gpg --import .gnupg/secring.gpg
-source /etc/environment
-domain=example.org
-docker run -it --rm --name test -h backup.container -v /root:/root -v /data/domains/$domain:/backup indiepaas/duplicity sftp://${BACKUP_DESTINATION}/$domain /backup
-
-systemctl start service
-docker run -it --rm --name mysqlinport -v /data/domains/$domain/mysql/dump.sql:/tmp/dump.sql --link mysql-$domain:db indiepaas/mysql /bin/bash
-mysql -u admin -p -h db < /tmp/dump.sql
-```