Dynamic mergekey PAZ-868
Commit proper test result for dynamic mergekey
Allow mergekey to be given for command=search
Clear relevancy info when result set is clear'd
Fix regression for mergekey creation

Due to xmlNodeListGetString returning null on some platforms
and empty "" on others (probably depends on Libxml2 version).
HTTP server: host=@ listens on IPV6 and IPV4 if possible

Also, allow ports to be given as names (not just integers).
Fix @-notation on systems that don't support IPV6 sockets.
Wait for separate session bytarget response
tests: poll for stable results

For results we wait for, repeat command until it matches against
a stable result.
XML context for errors, no set element for service

It's not implemented.
marcmap: fix type for ch in use of getc

getc returns EOF (usually -1) on EOF, so we must be sure to
use a type that can hold it.
Merge branch 'master' of ssh://git.indexdata.com/home/git/pub/pazpar2
marcmap: fix for fopen fail
Fix signed/unsigned checksum problem PAZ-871
Use sockaddr_storage in accept call PAZ-872

Due struct sockaddr is not big enough for IPV6 stuff.
Stable results (activeclients=0)
Minor refactor of session_sort_unlocked
Adjustments to log msg of session_sort_unlocked
Dynamic ranking PAZ-869
Test using dynamic rank
Show attributes in xml_context function