fix adress check

stacking negations is a poor idea...
another strategy to find USB printer serial

closes: #2213
Merge branch 'master' into 2.3.x
document additional changes
no man pages for perl modules
oops, fix module name
drop spurious invisible characters
oops
Fix dictionary update handling

This reverts commit aff2d8773fa2def45aecfaca12cdc8487bf8364f.
yet another change
yet another identification rule
more sysdescr normalisation
more sysdescr normalisation
more changes
use sysobjectid for vendor identification
'Hewlett Packard' -> 'Hewlett-Packard'
Dlink -> D-Link
new case
only apply relevant parts of matching rule
anything with 'JETDIRECT' is a printer