Add more specific lvm2 version to PACKAGERS document

I personally tested this using our container, and this was the lowest version that compiles and runs properly.

Docker-DCO-1.0-Signed-off-by: Andrew Page <admwiggin@gmail.com> (github: tianon)
Update docker_remote_api_v1.8.rst

Docker-DCO-1.1-Signed-off-by: Jean-Baptiste Dalido <jbdalido@gmail.com> (github: jeandalido)
Update docker_remote_api_v1.7.rst and non-versionned

Docker-DCO-1.1-Signed-off-by: Jean-Baptiste Dalido <jbdalido@gmail.com> (github: jeandalido)
Use '-s empty' instead of '-s dir'

This *should* have the same effect as the previous strategy: Instead of
'mkdir empty; fpm -s dir -C empty ...' we can simply do 'fpm -s empty'

Docker-DCO-1.1-Signed-off-by: Jordan Sissel <jls@semicomplete.com> (github: jordansissel)
Merge pull request #3555 from jordansissel/patch-1

Update Ubuntu packaging script to use 'fpm -s empty' instead of 'mkdir empty && fpm -s dir -C empty'
Merge pull request #3500 from tianon/lvm2-version

Add more specific lvm2 version to PACKAGERS document
Merge pull request #3539 from jeandalido/patch-1

Update docker_remote_api_v1.8.rst
Add linked containers name to etc/hosts