Lintian error fixes

Fixed:
synaptic source: native-package-with-dash-version
synaptic source: patch-system-but-no-source-readme
synaptic source: ancient-standards-version 3.7.2.2 (current is 3.9.5)
synaptic: debian-changelog-line-too-long line 3
synaptic: old-fsf-address-in-copyright-file
synaptic: copyright-without-copyright-notice
synaptic: binary-without-manpage usr/bin/synaptic-pkexec


Overridden (see debian/*.lintian-overrides):
synaptic source: more-than-one-patch-system
synaptic: desktop-command-not-in-package usr/share/applications/synaptic-kde.desktop synaptic
synaptic: menu-command-not-in-package usr/share/menu/synaptic:5 x-terminal-emulator