Many small changes, all withing the Debian folder

I hope this pull request is better suited to your needs. It is a bunch of well commented commits, only affecting the Debian folder. 

Lintian is still giving me the following problems with the packages:
W: sddm: extra-license-file usr/share/doc/sddm/COPYING.gz
N: 
N:    All license information should be collected in the debian/copyright
N:    file. This usually makes it unnecessary for the package to install this
N:    information in other places as well.
N:    
N:    Refer to Debian Policy Manual section 12.5 (Copyright information) for
N:    details.
N:    
N:    Severity: normal, Certainty: possible
N:    
N:    Check: files, Type: binary, udeb
N: 
W: sddm: package-contains-upstream-install-documentation usr/share/doc/sddm/INSTALL.md
N: 
N:    Binary packages do not need to contain the instructions for building and
N:    installing the package as this info is not needed by package users. If
N:    the info contained is important for configuration perhaps it could be
N:    summarized in README.Debian, otherwise an override may be added.
N:    
N:    Refer to Debian Policy Manual section 12.3 (Additional documentation)
N:    for details.
N:    
N:    Severity: normal, Certainty: possible
N:    
N:    Check: files, Type: binary, udeb
N: 
E: sddm: duplicate-updaterc.d-calls-in-postinst sddm
N: 
N:    The postinst script calls update-rc.d several times for the same
N:    /etc/init.d script.
N:    
N:    Severity: important, Certainty: certain
N:    
N:    Check: init.d, Type: binary
N: 
E: sddm: duplicate-updaterc.d-calls-in-postrm sddm
N: 
N:    The postrm script calls update-rc.d several times for the same
N:    /etc/init.d script.
N:    
N:    Severity: important, Certainty: certain
N:    
N:    Check: init.d, Type: binary
N: 
W: sddm: maintainer-script-ignores-errors config
N: 
N:    The maintainer script doesn't seem to set the -e flag which ensures that
N:    the script's execution is aborted when any executed command fails.
N:    
N:    Refer to Debian Policy Manual section 10.4 (Scripts) for details.
N:    
N:    Severity: normal, Certainty: certain
N:    
N:    Check: scripts, Type: binary
N: