daemon/lua: add support for resizing packets

mentioned in commit f218c571

assigned to @vcunat

added 25 commits

• 0f1b85aa...3de76924 - 24 commits from branch master
• 48e1143a - daemon/lua: add support for resizing packets

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merged

mentioned in commit f121fe55

@vavrusam: the new resize function won't always work correctly. The problem is that we're breaking API of knot_pkt_t, e.g. you can't always just change .wire address, because different parts of knot_pkt_t may hold pointers inside there.

That's probably why the new tests fail for us sometimes

kresd: libknot/packet/rrset-wire.c:246: compr_put_dname: Assertion `wire_pos < KNOT_WIRE_MAX_PKTSIZE' failed.

Our tree still doesn't use that new function, so "we're safe", but it still seems risky to keep this function as is over longer term.