add merge-v3:

+ call with installed-packages+ . installed-sources+ [ . available-for-build-packages+ ]
+ can cope with any filetype (including compressed)
+ allows to specify installed packages which are not available for building (and the other way round)
+ does quinn-diff internally, for that:
  + add WB/QD.pm plus testcase in tests/qd.pl
+ reads packages / sources only once
+ uses edos to resolve dep-waits
+ respect $simulate

enhance call_edos_depcheck:
+ add possibility to check depwaits (flag depwait)
+ respect $simulate