update mms-agent to version 2.+, using the new deb package.

this means the installation can be greatly simplified
add uninstall recipes to ease integration
doc update
feedback: doc fix
better uninstall
update to newest backup agent
factor out version string to ensure upgrades will get installed
Merge pull request #10 from Kabam/update-mms-agent

update mms-agent to version 2.+, using the new deb package.