Demote MAX_FD Log message from ERR to WARNING, since the array is grown if needed.
Removing buggy undocumented feature ...

... according to discussion at
https://github.com/jimis/core/commit/d4999f291bf937ef36ee05c28149ca773b172865
Changed message wording to be symmetric with 'accepting connection'.
Changed server's reconfiguration message to NOTICE so that it's always logged in syslog.
Renamed file to follow convention.
Fix "suggest parentheses" warning.
Demoted message about internals to DEBUG.
It was being checked as a bool but was returning int.
Added missing include, Solaris was failing compilation.
Test for isfinite().

Fixes compilation on Solaris 9.
All our [v][f]printf() calls have now C99 replacements in libcompat.
Update HACKING.md to reflect C99 status.