Upstream version 0.5.0

Upstream version 0.4.9

Thanks: Pali <pali.rohar@gmail.com>
LP: #1015131

Thanks: hawken <haakonsh@gmail.com>
Closes: #682395

Closes: #644630

Thanks: Rob Verduijn
Closes: #619353
LP: #727011

Thanks: Ivan Borzenkov <ivan1986@list.ru>
Closes: #589167

Since Lucas' build enviornment running 'lsb_release -sc' returns 'n/a'
for some unknown reason we have to take this into account during build to keep
FTBFS bug reports being filed.

thanks: Lucas Nussbaum <lucas@lucas-nussbaum.net>
closes: #634591

LP: #649364

Git-Dch: Ignore

Git-Dch: Ignore

Clean-up auto-generated files causing issues for piuparts testing.
Removes clean.sh, postmirror.sh & apt-mirror.lock if they exist
when a purge of the package has been requested.

Closes: #455106