Updates to manual uninstall for Ubuntu Upstart Service.

Add /etc/init/waagent.conf to list of files to be removed in Uninstall()
WALinuxAgent 1.3-PREVIEW

Merged changes from private-master branch

Changes:

Report Error and fail provision on empty hostname
Remove redundant checks during construction of LoadBalancerProbeServer.
Ubuntu Upstart Support
Retry loop for DVD mounting mitigates possible mount failures found during stress-testing.
Update Changelog
WALinuxAgent-1.3
Typo fix (suceed -> succeed)
Merge pull request #7 from ivoks/master

Typo fix